This is a discussion on Buy Apple TV 3? within the Apple TV forums, part of the Internet TV Devices and Peripherals category...
If you're already deep in the Apple universe, then it's the one you'll probably be happiest with.
I bought both. I'm still undecided with which one I'd choose over the other.
On one hand, the Apple TV so easily syncs with my iMac, iPad, iPhone 4 and the user interface is simple and familiar. On the other, the Roku has almost endless possibilities for adding new content for little cost or free.
My intent was to buy both and then sell one, but now I'm thinking of keeping both for separate TVs.
One thing I guess I can add is, be sure that you collectively purchase and use the same account for all of your iTunes stuff if you plan on buying an Apple TV. One of my friends just bought the 3rd gen and is having problems with Airplay because half of his stuff is on one iTunes account and half on another. He's emailed Apple about it and basically seems to be SOL because Apple refuses to allow transfers between accounts. I like Apple but that's just wrong.
BTW, I wish Apple would have added volume control to the remote. I now have 4 remotes in my bedroom for controlling home theater equip.
collecting Roku channels over at http://catastrophegirlsrokuchanneldata.blogspot.com/
isp/speed: TWC cable internet/20mbps
streaming devices: Roku N1000, Roku1 XD/s, Roku2 XS, Dell desktop PC, Toshiba netbook
subcribed to: Netflix, Hulu Plus, Amazon Prime