Ok I thought my issues with trying to put my pb into standby mode might have been fixed with this latest update but no luck. When ever I try putting it into standby mode it only shuts off for a few seconds then the screen comes right back on and it does this cycle non stop draining the battery. Something appears to be activating the screen.
Does it only do this in a certain places, or everywhere all the time? It is capacitive touch so any strong magnetic fields will cause it to go whacky. You can search on tesla coil and see a video of a Playbook with a Tesla coil near it making it go nuts. It it's happening everywhere then it sounds like your screen is messed up.
You still have a warranty. There was a post yesterday that BestBuy (Canada only???) would cover them for 1 year. I don't know if it is true - I believe the post was about a pixel problem.
There have been posts about standby mode still looking for wifi and bluetooth connections. I was having relatively short battery life even while on standby (fully drained in a couple of days with no use). When I turn off wifi and bt before going to standby, much better.