Since I can't decide on what to do, I've just been making new characters and running through the first 5 levels in the new starting areas. They're very well done. A smooth introduction to the game, and several deft nods to experienced players.
Orc - They're introducing the human/orc conflict really early. It's an interesting choice. Otherwise very similar to the old version. Waking lazy peons is still the highlight of the early orc experience.
Dwarf - Nicely streamlined, with integration of the Dark Iron mages and warlocks. Of course, everyone rolled dwarf shaman. I don't think I saw a single dwarf mage or warlock.
Night Elf - They only make you run up to the top of the tree once, at the very end. And they give you a Slowfall buff so you can jump down! As well, the moonwell quest lore is now more in the game world, rather than quest text.
Tauren - The quillboar killed the Greatmother! I liked this the best of the starting areas I tried.
Gnome - Very well done. An interesting story, and lots of gnomish moments. Oddly, this was the hardest starting area. I almost died several times fighting troggs, as they hit hard and I kept getting attacked by multiples. They also have a knockdown, which didn't help. (I was playing a priest, so was a little squishy.) I did actually die during the final battle, as I got swarmed with little guys, and didn't use the special device properly, I guess. Still kind of shocked that I managed to die in the first five levels.
Haven't tried the others yet, but I probably will give the rest a whirl tomorrow.