WHAT ARE THE SIGNIFICANT CHANGES?
1. We finally have an Apple laptop with four cores -- kina sorta. It's really a dual-core processor with built-in Hyper-Threading that allows two threads to run simultaneously on each core. Mac OS X recognizes four virtual cores instead of just two. Though the top core frequencies are down (2.66GHz) from the top end Core 2 Duo (2.8GHz), the performance should be much better. Don't forget that the Turbo Boost can take it as high as 3.33GHz.
2. The GPU has been upgraded to a GeForce GT 330M with 48 cores and 512MB of GDDR3 video memory. The previous top model had a GeForce 9600M GT with 32 cores and 512MB of GDDR3. Both are in what NVIDIA calls the "Performance" category of mobile GPUs. However, there are faster mobile GPUs made by NVIDIA such as the GTS series ("High Performance") and GTX series (Enthusiast).
3. The built-in battery is rated for 8 to 9 hours. (That's up from 7 to 8 hours for last year's MBPs.)
4. The 15" now offers the choice of 1440x900 and 1680x1050 display resolution. (The previous model offered only 1440x900.)
5. Storage options now include a 512GB Solid State Drive for a mere $1300. (For $200, you can still get the 500GB 7200rpm HDD.)
WHAT THINGS REMAIN THE SAME?
1. The ExpressCard/34 slot is still only available in the 17" model. The 13" and 15" models get an SD slot.
2. The 17" still supports 1920x1200 native resolution.
3. The choices between glossy and antiglare LED-backlit display.
This is a welcome upgrade for those who use their MacBook Pro as a desktop surrogate. The Core i5 and i7 processor means that you can expect better performance from demanding apps like Aperture, Compressor, Photoshop, and After Effects. What constitutes "better" will be judged when we run our suite of benchmarks, comparing it to not only last year's MacBook Pro but some desktop Macs.
We still wish the 15" model had an ExpressCard/34 slot.
And how about an "Enthusiast" MacBook Pro with NVIDIA's fastest mobile GPU, the GeForce GTX 285M? (See NetBookCheck for a comparison of the GeForce GT 330M and GTX 285M running 3DMark Vantage and various 3D Games.)