Text from my review of Fanball.com as heard on Extra Points podcast.
I've used fanball.com as a user for the last 2 years for 2 different leagues.
Our Commish switched from CBS Sportsline.
Its very comparable to the big guys, plenty of customization for rules and points, live chat, online draft and live scoring.
The cost is about $120/year per league, but it will also keep the league from intact for the next season, making keeper leagues easier to maintain.
It also has a stats section which gives you a head-head scoring comparing your score to all other teams and also maintains hall of fame stats spanning the seasons and playoffs.
They have an active writing staff to help you decide who to play trade or draft. Like Yahoo and CBS, fanball is designed for fantasy sports. They have multiple football games and are setup for fantasy baseball, basketball, racing, golf, sports book and poker.
One downside which shows it hasn't been ready for the season is the live scoring in the beginning of the season. Fanball has had two different live scoring apps the last two years, and in the the first couple of games of the season, the web site can't seem to handle the traffic load, especially at halftime and between the games when people tend to check the scores. 404 errors were common. During the rest of the season the live scoring, although live scoring being unofficial would be incorrect. There were a couple of close games I was up or down by 3 points Monday night only to find I won or lost by 10. The message boards were loaded with threats of people switching to other sites. To there defense, CBS has had these problem in the past as well.
However, I still prefer yahoo's paid service over Fanball.