said by pike:"Not believing in using wifi" is a preference with no empirical data backing it up. Also you're missing out on one of the biggest selling points of the Apple TV: AirPlay.
No, the differences in performance of a wired gigabit connection vs a 802.11n wireless connection are well documented - especially when dealing with video streams. The unknown is how 802.11ac will affect that comparison, but any comparison using the current revision will soon become obsolete with the next generation chips. Wireless provides convenience, it will never be able to match wired for performance - the only debatable fact is how much that matters.
AirPlay works just fine over a wired connection as well.