Ok here goes:
Having experienced both of the programs well past 30 times each, I have found that each of them have their flaws and their advantages. Carnival's program fluctuates GREATLY from ship to ship. Until recently when the program switched to the Youth Activities branch of the company as it's management team, the Club O2 program had a lot of flexibility. What did this mean? Well the directors had a lot of creativity and "say" in their schedule but unfortunately many of the abused it and that led to the switch of Club o2 from entertainment to camp carnival. Since that switch, I've noticed that the directors themselves are more stressed because of the bosses breathing down their backs more than they're used to, and it really reflects in their performance. Also, Carnival's directors are VERY passive. Carnival doesn't seem to keep many of their staff for too many contracts. I can recall sailing on on ship in particular 4 times in 2 months and every time having a new director and that was during a high count period when a strong, solid director was needed to keep the program organized well. In addition, Carnival's programs have no particular requirement for employment. Obviously every application for a youth staff position is reviewed carefully, but there comes a time when we must wonder just what qualifies you. For instance, Dan Polulak was 18 when he began as a Club O2 director and he is, much like me, a very mature and intelligent 18 year old...but its still important to remember that the difference between 17 and 18 is a year at BEST and unless you are a very strong individual, its hard to keep the respect of the teens as a young director and I've seen that fail many times.
Thats a lot of negative on carnival, I know but heres the good part. Carnival spends a lot of time putting thought into their teen program and have really built something unique with the design, location and structure of their clubs. One thing that Carnival has over most of RCI's (and other lines as well) clubs is their positioning. Most of Carnival's clubs are on the Promenade deck which greatly increaces the likelyhood that teens will be enticed to at least consider participating. Carnival's clubs are well outfitted with decent sound and lighting systems that are capable of handling the levels of teens that come through, whereas Royal Caribbean's Fuel/Optix and Fantaseas clubs utilize much smaller EAW and Meyers sound rigs that are really designed for install in public areas for background music. Carnival also builds their program based off of the input from their teen passengers. Club O2 directors, in my experience, are far more likely to alter the schedule if the teen group is interested in doing something else. Carnival's directors are also able to relate to teens far better than RCI's. Carnival seeks younger, more energetic individuals whose interest is in working with TEENS 15-17 and not just drafting a member of their youth staff to "work teens" for the week.
Royal Caribbean's programs are developed in an entirely different method than Carnival's. Their programs are developed with the company "theme" in mind. Royal Caribbean is, an has for a long time, been known for their "adventure" theme found throughout the fleet. Their emphasis on activities onboard all ships like the flowrider, basketball courts, rock walls and sports & lap pools are just part of their program. Fuel/Optix/The Living Room/Fantaseas all have teen activities and directors who work closely with the Explorer Academy and Vitality programs to develop teen activities that open new opportunities for teens. The problem with this is that it's executed to different levels on different ships. On Voyager class ships, they host Scratch Academy 101. Voyager class vessels DO NOT have an onboard Scratch DJ, therefore the program is usually taught by one of the onboard DJs or the teen director. Both are talented but many simply do not posess the knowledge of the equipment in such a specialized field well enough to be instructing. Royal Caribbean's directors are another vice to the sucess of their program. Many of the "teen directors" onboard RCI ships are nothing more than youth staff. On the plus side (legally) though, teen directors for RCI must be 21 and possess a college degree. A teen specialist is usually onboard most of their ships, but it isn't guaranteed and without a teen specialist, theres no guarantee that any of the programs will be executed correctly or at all. Finally, Royal Caribbean has very...bland teen areas. On many of their larger ships, the teen club is less than 50 feet from the Aquanauts room for children 18-36 months and is actually next door to the voyagers room for 9-11....Not "Cool". Many of their teen centers are copies of eachother which...the intention is to create brand quality through the use of a continuous model throughout a class of ship, but from a teen whose been on many different ship...a different design isn't so bad every once in a while. Finally their clubs are usually located on the top, back of the ship away from all the common areas. Yes, the intention is to keep "undesirable teen activity" contained to an area that can be better controlled by deck officers and security should the teens become "rowdy", this way they won't disturb other guests....however I have a problem with that when theres no containment design for keeping the drunks away from teens who are just trying to enjoy a common area of the ship.
On the positive side, Royal Caribbean has instituted many new and innovative programs on their ships over the past couple of years. The DUSK and WAREHOUSE theme nights are awesome (when done properly) and their activities are usually unique over the ever common, battle of the sexes and dating game. Additionally, they've added unique concepts to their fleet like the "Fuel Unplugged" concept on ALL ships which provides 2 Electric Guitars, A Keyboard and an electronic drumset on each ship and lets teens who can play (and those who can't) jam out on real instruments rather than just video games. Most ships have also invested in professional versions of the rock band and guitar hero units which were designed to take a beating and use more metal than plastic. Also, many ships have full sized, metal DDR floors for competitions and more.
In conclusion, I think that each program has much to offer a teen market. I personally think that Carnival has and always will have a better teen club for strictly dancing and evening activity and I think that RCI will have a better program when it comes to "activities". Many teens are looking for a better evening experience and therefore, I belive that Carnival's programs will be more sucessful in pleasing their target audience if they continue to pursue innovation in their program. I tried to write this in an unbiased form, especially given my connection to carnival and the program.
I hope it provides some insight not only for the OP, but also to those of you who have questions about the programs.