I've only had mine for a few hours, but I already like it a lot. I've always purchased matte screens in the past, but even I can't deny how amazing the display is. The viewing angle and colors are so much better than the matte LED displays of the previous generation.
The keyboard is probably my favorite part. The keys were too close together on the previous model, and I found myself hitting Shift + Up Arrow while typing, thus causing me to type over the previous line. The spacing and feel of the new keyboard is so much better.
The trackpad is excellent. I love gestures, especially with Multiclutch. I totally dig the "no button" thing. It works fine. The click is extremely noisy and doesn't recognize presses made with the entire width of your thumb, though.
The build of this machine is so much more solid than the Powerbook relic case of the previous MBP. The screen is lighter and extends back further, the machine feels like a solid brick when closed, the sleep light is much more subtle, the upgrade process is so much more streamlined...(although I find it harder to get the battery cover back on).
It's not perfect. I miss Firewire 400, and I wish they could have added a third USB port. But it's still an amazing machine, and as Ive said, it's much more than just a collection of parts.