I did the Voyager Dec 15 2001. The crowd was a very good mix. There weren't alot of kids (probably had something to do with being right before holiday break). I saw a lot of 2 and 3 generation groups. I am in my mid 30's and was traveling alone, at our dinner table there were 6 of us in our 30's traveling alone, a couple in their 50's who brought his 70's mother, a woman who was in her late 80's and a couple in their late 20's.
I don't know what your previous sailing experience has been, but it is a younger crowd than your typical Celebrity cruise (by a lot) and just slightly younger than Princess.
Out of all the cruises I have been on, the Voyager had the largest cross section of demographics.
Hope this information helps.