I was kind of on the fence about 1-2-1 vs. 1-1-1 movement before I did my playtest of 4e last weekend. I found it made a dramatic difference in play.
It made movement much faster for one thing. I just started moving and BAM! I was done. I didn't have to try to remember if moving diagonally was my second diagonal or my third or what. I just moved. Score 1 for WotC.
Only one wonky movement scenario came into play during the whole session, when a player moved around some caltrops I had on the ground without movement being affected. Score 1 for 1-2-1 traditionalists.
But overall, 4e movement just felt more dynamic. As strange as it sounds, not having to treat diagonals in any special way actually made the game feel more cinematic and LESS wargamey. I didn't expect this at all. It really became noticeable when I went back to 3.5 movement rules later that night for my Pathfinder game. It suddenly felt like all my monsters were wading through molasses, or were wearing ankle weights. The game felt much less cinematic and more like I was playing some sort of tactical wargame.
I expected 4e movement to feel more gamist. But the opposite was true. At least for me. I think it has to do with the fact that counting squares in 4e required almost no mental effort. You just moved. Beyond counting squares, no mental effort was required. You could pretty much move on auto-pilot. As a DM, this freed up my brain and allowed me to think ahead about other tactics, it also allowed me to describe and narrate the action while moving the monsters.
In 3.5, movement requires your brain to track three things simultaneously: feet to square translation, total squares moved, and total diagonals moved translated back to squares. Now, this doesn't require any strenous effort or anything but it is distracting enough that when I move I have to concentrate on movement. I can't narrate the action. I can't think ahead to the next monster until I'm done with the current one, etc.
If you can, more power to you. But I'm not good at multi-tasking. For example, I can't really talk to my wife while driving (much to her annoyance).
So for me, its point and match for WotC. I will use 4e movement as written and I think my game will be better for it.