I just "upgraded" my iPad3 to ios6. Performance is fine, my battery drain when not in use is insane. I lost 50% charge while not in use over a half day or so. I thought it was weird but didn't think much of it. Plugged it in overnight for a full charge, got back to 100%. Didn't use it for two days and now its completely dead. Normally would have only lost a couple percent. Wasn't even connected to wifi, I'm very unhappy.
Not even on wifi? Weird. I know that my iPad seems to be sleep draining a little faster than normal, but I just assumed that was background stuff, you know, doing stuff.
Performance wise, almost no differences between iOS 5 and 6 for me on either of my iDevices, and the new Maps app is just fine for me so far. But I don't use my phone like that all that often.
Honestly, I think that the new connector is nice, I wish there was a way I could upgrade to it. Other than dirty, dirty corporate greed, the micro USB spec doesn't support the amperage that the iPad requires, that and is ultimately a dumb connector (dumb as in not smart, not dumb as in lame/weak/stupid)