It's not supported much after the release of the next version, but much more than any other system to date. It's not just sports games either. Persona 3 was released before the PS3 in Japan, FES, that included additional content was released afterwards. I'm pointing out Persona 3 only because work on Persona 4 probably didn't start until after Persona 3 was finished or later. Persona 4 was released in 2008, almost two years after the release of the PS3 in Japan, past two years in the US.
The PS2 got a decent amount of support compared to pretty much any other console. Something we can compare right now is the DS. At the same point in time after the release of the previous console, the PS2 was still getting a somewhat decent amount of games. Most of them may have been multiconsole titles or ports, but still getting releases all the same. It did get its fair share of exclusives as well, though.
Off topic, but check out the releases coming out for the PSP. For PAL owners, unless you import Gungnir, Growlanser, and probably Persona 2 from the US you should move along as there's nothing more to see. Even sports games don't make the listing, but they do in the Japan listing. Looking at the Japan release list and
. The Japanese really love the PSP.