The research seems to indicate that it is safe and effective with lots of benefits apart from those related to sports performance.
I found some of the comments on the Heart Scan Blog post about creatine to be interesting - lost of positive testimony.
The comment to this blog about the benefit in terms of muscle soreness was timely too. I've been very sore after a Krav Maga session this week!
Anyway I am taking creatine again (despite what I wrote here) for a while to see how it goes.
(Update, Mike points out other recent research)