Well I personally think Endermen are a tad disappointing. The real scary mob is undoubtedly the Silverfish although I don't know if they've been implemented yet. I spawned some on Jolt's server and it looks as if they hide in something that looks like stone blocks but appear once you destroy said blocks. Creepy as hell.
I <3 Melons, they're easy to farm, a bit rare to get some actual seeds though :/
NPC villages are so far my favorite feature(Even though there aren't any NPC's yet.) I found a village in a desert on Blocktopia's test server. It was fun for the short while that it lasted and Jolt and I made the village look awesome and surrounded it with cacti. By the time that the test server was taken away 3 more people had joined our village named Cactopia.
I never realized how slow I was until sprinting came out. It also gives me the opportunity to critical hit mobs which is pretty damn awesome. You can also now use your sword to block attacks(a feature that seems not many people know about) The new bow animation and critical hit shot is awesome, it now only takes two shots from a bow to kill a creeper. This does make it a tad too easy though :/
Abandoned mines are pretty damn cool as well. Poison spiders are a cool new addition and perhaps a bit too powerful. I almost died twice while stumbling upon a poisonous spider spawner. :/
Ravines are pretty awesome and gets you materials like iron fast but it's somewhat dangerous to descend or explore at night.
Furthermore, little things like edible beef and chicken is what makes the update great and perhaps the best update so far. Chests also have a new model and opens up when in use like a real chest. Giant mushrooms aren't found in the wild yet but can be obtained by using bonemeal on a mushroom. This spawns a giant mushroom which drops more mushrooms when destroyed. There are also supposed to be strongholds but I've yet to see them :/
My only criticism so far is exp orbs. To me, they are useless and always will be. They're extremely buggy and they serve no purpose and I hope Notch gets rid of them.
If this doesn't get you back into Minecraft, nothing will.