Should I buy an XBox 360, or wait for PS3/Wii?

[Hoya]

I've started to get a hankering for a new system, and I have a feeling other people have this same question. Here are the relevant facts about me:

1 - My last two systems were the PS1 and 2 - I liked both.
2 - I mostly play sports games, but will sometimes get other games, although usually ones that are geared toward an "older" audience
3 - Online play is important to me
4 - I don't care about Nintendo franchises
5 - Cost matters, but it wouldn't stop me from buying, say, PS3