It's slow at work, I haven't come round here in awhile, and I'm sure this will get ignored, but I'll just think aloud here for a second:
From what I gather, the distinction with Greece is that their town meetings court--at least in theory--constituents who have come to petition, et al.
In that spirit, taken in a vacuum, I don't agree with the decision, but here on planet Earth, I have no problem with it.
As I understand, prayer bans at town meetings like those in Greece are meant to facilitate a process of government that doesn't alienate those non-elected officials who have come to participate. But, since we're talking about Christian prayers, I have to question to what degree someone would be truly alienated from the process.
If instead the prayers were some bizarre, in-tongue incantation that involved dancing, screaming and an appeal to some monster-god (perhaps pasta in nature), then yeah, I could see alienation being an issue. But I don't think a quick, 20 second Christian prayer, in the spirit of tradition (as Kennedy argued) will throw too many people that far off their game.