I'm was really on the fence about ordering one, as my aTV3 with PlexConnect does pretty much everything I want and I wasn't expecting a Plex app on day one.
Whilst there is lots of room for improvement, I think those shouting about sending it back on Monday are being somewhat harsh and its no where near that bad. It's a step up from the aTV3 and the potential now it has an App Store is huge. I'd bet before Christmas there are some really great apps available, doing a lot more than the previous model could.
I'm sure some people just like to say they got one on launch day and are looking for any reason to return. Apple really should review its no quibble returns policy where the justification is I've just changed my mind. People should have expected some day 1 issues and be prepared to give it a few updates, not looking for excuses to return within 14 days.