Hi. I didn't see my bug written here... hope i'm not repeating smth someone else wrote.I'm not sure of all the cases in which this bug occurs but here it is :
I'm starting a game from the MS, and as all you know, there's the PSP animation before the game starts. If you press the Home button when the animation is activated the vsh menu appears, and then the PSP gets stuck and you have to shut it off and turn it on again to pass this.