Go to the web site: http://www.oceaniacruises.com
They are fantastic. I went on a cruise last summer and I am going again this summer to the Baltic. They acquired two of the old Renaissance ships, with nearly the same decor (new beds).
They have 4 restaurants on board (for 600 passengers). The food is excellent.
They spend a LOT of time in port. On our 12 day cruise we only have 2 sea days, They do a lot of overnight stays. We have 3 full days in St Petersburg.
They consider themselves to be in the luxury category, but they are not exactly like other lux ships. The cabins tend to be a little smaller, and there is not a lot in terms of onboard activities. Entertainment is at a minimum, which in my opinion is fine because they give you so many evenings in port. They do have a great computer program if you want to take classes, etc.
The focus is on good food, small ship convenience and excellent destinations at a respectable price.