I dunno about ps1 games, but its only suppost to be 200 out of 8000 PS2 games that dont work.
This isnt bad at all percentage wise.
Its the whole cant display anything but 1080p or 480p that suck at the moment, you pack in a bluray player you expect the HD to be tested.
Sony have said this will be fixed in the first update and i imagins backwards compatibility will be fix at somepoint.
I expect many updates will have happened by europe launch, so we should get a pritty stable system which is our only benifit.