Both Magnetic Joes (the 1st and 2nd one) in the update description mentioned it was going to install an ad system into the game, so I forgone them. One game was switching to (not also adding) Game Center support. GC won't recognize achievements unless you're logged in, and I'm only logged in at home where I have a wifi connection for my IpT, so wasn't going to do that. In the end, it didn't matter with some of them, as when I switched from my IpT3 to IpT4, their save data didn't make it over, including Magnetic Joes 1 & 2 It'd be nice if you could go into "edit mode" for the Update list and check/uncheck the apps you want to include/exclude, THEN tap the Update All button.
