I have a April '06 2007-63U (as per my sig) and work just gave me a new 1951-XXX.
I'll compare my differences with yours:
gator wrote:1. The new machine is a rock, as always. The keyboard seems to be like the old NMB ones (which surprised me a lot), with a fantastic response and great travel almost close to my X31 keyboard. My machine also has a supposedly NMB keyboard, but after seen the new one, I have my doubts

Seriously, the new keyborad is excellent (and I am picky).
Check. My old keyboard was a Chicony. The new one is NMB. They are about the same in terms of key resistance, but the Chic is very noisy -- you can type almost silently with the NMB. All the keys/buttons (including the trackpoint buttons) feel much more solid than the Chic.
gator wrote:2. Though this is a minor point, I'll jot this down. Hje latch on the lid is back to the defualt black color compared to the silver on mine. It looks very neat. (Thanks for listening, Lenovo!)
Check. Though I kinda liked the grey latch. Also, the retro black latch is also a lot harder to "click" into the locked position. I don't like this because it feels like the extra effort means my fingernails will scratch off the paint around the latch.
gator wrote:3. The battery does NOT wiggle one bit (6 cell AND 9 cell) in the new one and it does not say it if SANYO or PANASONIC etc - it says Lenovo!! (My battery has a sanyo label on it) - has Lenovo started making batteries
Check. My old Panasonic 6c needed some tape to make it solid. The new 9-cell Sanyo is a perfect fit.
gator wrote:4. The keyboard bezel is slightly beefier(and very, very solid) near the hinges and looks lightly different - infact, in comparison, mine feels slightly flimsy now in comparison

Not sure what you mean by this? They both feel the same to me. Though the annoying "click" has gone when you push down on the left edge of the palmrest above the expansion slot.
gator wrote:5. The palmrest has the same issues fixing it - it is impossible to put it right at the first go. I wish it were easier like in the 14" models.
I've never had a problem with the palmrest fitment. The new one is the same.
gator wrote:6. The power and the volume buttons DO NOT feel flimsy or cheap - beleive me, the old school power button feel is back. But I really wish they bought back the earlier design for these, they were much much better.
Agree, kinda. These buttons on the NMB keyboard feel *slightly* better. Not like the trackpoint buttons which are HEAPS better.
gator wrote:7. The screen is gorgeous, as always. No grains, no difference from my BOE HYDIS panel (the new one is a samsung). Colours look just the same, I cannot tell them apart at all whatever I do. After seeing some complaints about sparkly display, I was expecting some difference, but the screen is gorgeous.
The new screen is a TMD 14.1 SXGA+ and I don't like it. It is waaay too bluish compared to my Samsung. I have fiddled with the TMD a bit to try and make it redder/less blue without much success. This makes the TMD a little brighter, but after looking at the Samsung for a while, switching to the TMD makes my eyes hurt a little.
Okay, time for some of my own:
8. There is "lenovo" badging on the status lights area next to the "T60" badging.
9. The new hard drive is a lot noisier. It is a 7200RPM Hitachi, the old one has a 5400RPM Fujitsu. I guess that is to be expected from a slower drive, though in practice I haven't noticed the speed difference.
10. The Bombshell: after much deliberation, I have decided that the new Thinkpad is NOT BLACK.

It just isn't, compared to the old one. I don't know if it's something to do with the stipple texture on the body (which seems the same as my old one), but I am convinced that the new one is not black, it is dark, dark, dark grey. This 'greyness' is not isolated to the body, either: I actually became convinced when I swapped the new keyboard into my old Thinkpad and vice versa. The new keyboard is noticeably grey in my old Thinkpad. What's funny is that the function keys are darker than the other keys, so they seem black and the main keys are grey, the opposite of the keyboard on the old T4x!