I found this article and thought I'd post it here. It's a few months old though.
Fruits Basket Second Season
In the Q&A, Funimation Marketing Director, Adam Sheehan, answered a question on a highly anticipated sequel to
Fruits Basket - one of Funimation's most popular titles.
Unfortunately, as of right now, a sequel isn't in the works through Funimation has been pushing the Japanese to do a second season - and they are ready to finance it. Mark gave three reasons for the hold up.
1) The Voice Cast - Most of the voice cast has retired and they aren't interested in coming back to do a second series. They came out of retirement to do the first season. Coming out of retirement again is less appealing.
2) The Mangaka - Natsuki Takaya (the mangaka - creator of the manga) didn't like the anime's director, Akitaro Daichi. If they were to do a second season, Takaya would want to replace the director.
3) The Producton Company - Unlike Takaya, the production company,
NAS, likes Daichi and would want him to do the second season.
Adam claims they won't give up until they get a second season, but I'm guessing it won't be for a long while.
Source:Animetique