Not that I can recall.
Really? Cause I could hit the PS button on my controller and bring up the XMB. I could press the guide button on my 360 and bring up the mini dash.
And what happened when you tried to get to certain services?
It wouldn't let you access them and you'd have to back out to the real dashboard, that won't be the case this time. There is going to be no diminished features when you are playing a game.