He is still playing, but will likely play less and less as time goes on. He played in just 12 events in 2011, but had some medical issues that caused his schedule to be curtailed somewhat. This year he's played in 4 of the first 6 events, and is playing this week as well, although I know he'd love to be more competitive. Hopefully he's still got some good golf left in him. He'll be 64 in July, so his expectations are tempered by the reality of the aging process.
No matter how you look at it, though, he's had a fantastic record. Best of all, he's been very generous in donating to worthwhile charities, and he's a great person.