Excellent!
I was waiting for this announcement. Those PR with "to whom it may concern" really kill me, after the one for the 3DS last year ^^
June 2012 (probably Q4 in Europe) is a little far, but I think it will be fine. I will have plenty of 3DS games to play until then.
What is really exciting now, is that there will be new Nintendo games to discover at E3 for sure!
Zelda and Mario at heading to Wii and 3DS (maybe not if SS is delayed again like TP was at its time), so what IPs will be shown on Café? I can think of Pikmin, F-Zero, Starfox, and Smash Brothers...
I don't know if this has already be said, but Café controller + Virtual console == pretty much portable NES/SNES/N64 and all the rest. I'm looking forward to some good functionnalities here.