Uhh, dude.
First, YouTube's outages have nothing to do with Google. There have been many, many maintenance periods even before they were bought by Google (who run their servers using Linux, by the way). Secondly, YouTube only removes videos because they're legally obligated to, and that's due to how popular the site is, not due to Google. They would have had to pay Viacom one billion if they hadn't taken down numerous videos (some of which were actually innocent, but hey, that's capitalism for you).
On the whole blocking thing, YouTube is generally work-safe. Inappropriate videos are usually flagged and either removed or hidden from minors. Hence why it isn't blocked. DailyMotion, on the other hand, has some inappropriate videos that show up on the front page. This is likely the case with MegaVideo.