I have been kicked to XMB one time, it was a day or so after the latest patch, 1.03 I believe.
I've been playing Starhawk since early in the beta, approximately November-ish.
I bought the game launch day and play almost every day, I have almost 200 hours since launch and only the one kick to XMB.
I can not recall the circumstances of the kick, just that the screen went black while in game, then a few moments later I'm at the XMB. I think the map was Cypress.
Normally I get a PS3 freeze and have to restart, but since the latest patch this has only happened once in normal games, but I can no longer play split screen. Every time I try split screen the PS3 freezes as soon as the second player's pod bursts open/hits the ground. This happens even in Homeworld with just the two of us, which should be offline.
Seriously, there's just certain things that we must accept about the PS4. In time, it may get better, who knows.
**honestly if you still have your PS3.. and lot of games to go through.. there's no reason to jump onto the PS4 bandwagon just yet...
Now that I think back..... I had 1 maybe 2 freezes when I first got the game, but nothing since. It has been pretty reliable for me. I think I may have been xmb kicked once in basin.... I don't fully remember. I believe I was flying. Sorry I am not more specific. But I figure better to say something than nothing. It seems to be a regular issue for some players.