It doesn't matter how many apps there are if the apps you like don't run properly. I love my iPhone, but can't stand that Pandora and RSSPlayer won't run in the background while web surfing or reading email.
That's what I love about my TP2. While I haven't found a good Pandora app yet (I think they are out there, but with a bunch of compromises), I LOVE KINOMA PLAY. It's almost the ultimate media player (which it would automatically download podcasts though).
I love moTweets (great Twitter client).
The Microsoft Facebook application runs well.
I like RSS hub.
And I use Handmark express.
I agree with Big D. There will be plenty more applications coming. I think eventually if MSFT is able to re-invigorate demand for the platform the developers will come back. I've heard its much easier to develop for the WinPhone platform than the iPhone platform.