Just received my CTO Penryn MBP today, and I'm replacing my Merom (2.2) with it, as I had a few build quality issues with the Merom, so it's being returned to Apple (I craftily managed to hang onto it for 6 weeks until the Penryn was released, as I needed it for work, by constantly postponing the courier collection!). Anyway, some comparisons:- -It doesn't get anywhere near as hot! I've not really done much on it yet, just web/email/iTunes etc., but the problem areas for heat (above the keyboard etc.) are now almost cold, just slightly aired, whereas before (doing the same sort of things) on my Merom, it was "very warm" in places. -The penryn's fan (lowest <2000rpm setting) is a fraction louder, and it also has a faint constant buzzing coming from the right of the keyboard. Not really a problem, but does make it ambiently a little noisier. -My display (glossy) is about as good as before, with slight fading towards the bottom of the screen (apparent on most MBs/MBPs I think!), and ever so slight backlight bleed on the bottom (this is less than before). -The optical drive sound (that happens when you start up the computer, or wake it) is very different - it's more muffled, and lower in frequency than the old one, and generally a quieter sound. Strange! -The keyboard has a slightly different feel, a bit more positive and slightly less spongey, and also the coating on the keys feels a little smoother somehow... -Not sure if I just had a bad Merom, but the overall physical build quality seems a bit better on the Penryn - the lid now shuts a bit tighter, although there's still a slight gap, with the left a bit more than the right, meaning you can ever so slightly rock the lid when closed, but it's better than before; trackpad button now has a much softer physical click, and it's more sensitive. -Hate the caps lock "safety" feature now, grr. -Illuminated keyboard now more uniform across each key, and lights up much more of the key labels (rather than leaving dimmer areas), making it look more constant. -Love the multitouch, it works seamlessly, and is very sensitive. The trackpad is a little too small for it though, getting 3 fingers on there, and/or pinching is a bit limiting - I really wish they'd put the MacBook Air trackpad/button on there! And that's it - overall very pleased! As you can probably tell, I'm very picky, and this Penryn still isn't perfect, but it's much closer than the last one (apart from perhaps that "buzzing", but I should be able to live with it)!