My heart kind of sinks on April 1st because I know we're in for an avalanche of annoying, half-assed "jokes." That said, I do appreciate a good April Fools prank.
In my mind, these can take two forms: either they're something that might conceivably fool quite a few people (I don't understand the point of blatantly obvious false stories and the like), but are also clever and funny (so not just straight up lying about something boring or serious). Basically, if you can come up with a really ludicrous premise and still manage to present it in such a way that people are fooled. Something like this: http://en.wikipedia.org/wiki/Spaghetti_tree_hoax
The other good kind is when you go balls to the wall crazy and outrageous, but put loads of effort into it so that the audience is impressed and gets a bit of a laugh out of it. Like how a couple of years ago Destructoid turned the whole site into "Oktoid" - a terrible dating site aimed at gamers. That was genuinely funny, and you had to be impressed at how fully they committed to it. Similarly, stuff like disassembling a car and putting it back together again in an impossible place, like inside a school building (I can't for the life of me find a link now but I know this happened somewhere a while back) takes ingenuity and effort and can result in some pretty funny photos.
So yeah, kinda sick of a lot of April Fools, but the good pranks make it worth it. Sadly I haven't seen any really good ones today though.