Well, I’ve been playing with SL for about two days now after having installed it yesterday on my Penryn multitouch MBP. Here are my impressions of it:

• It is fast.
• Whatever new features it has are nice touches.

This wasn’t meant to be a flashy release. Very low-key on the outside, while architecturally, the changes are quite massive. To start, this is the first practical application we’ve truly seen of EM64T (AMD64, whatever) on OS X. As an aside, all these stupid “OH MY GOD! 10.6 BOOTS AN i386 KERNEL BY DEFAULT! APPLE IS SWINDLING US ALL! BUT LOOK AT HOW COOL I AM: I FIGURED OUT THAT IF YOU HOLD ’64′ IT WILL BOOT X86_64!!!111″ stories I’m seeing all over the place are…well…wastes of keystrokes. Who cares if the kernel isn’t running in long mode? All userspace components (libraries, executables) are! The small gains from forcing everyone to boot 64bit are deeply offset by the hundreds of 32bit kexts in use for which a 64bit build may not see the light of day for months. I booted my machine with the 64bit kernel…there really isn’t that much of a performance gain (though it is noticible). As an early adopter of amd64 back under FreeBSD when the Athlon 64 was fairly new (which was a bit painful, but worth the experience), I applaud this non-boneheaded approach to backward compatibility, with graceful fallbacks to 32bit mode. Note that I speak without having ventured into the braindamage that is Win64.

Anyway, I digress. In this release, everything is faster. Safari loads in 1 bounce. The time from login to the point where I can actually start using the system is much shorter. And, despite the changes in drive capacity measurement base, it did free up quite a bit of space. It’s probably the first commercial OS release I’ve seen where the base install was smaller than the that of the release that preceded it.

I eagerly wait to see what can be done with OpenCL and Grand Central Dispatch.  I also am pleased with Quicktime X; the screen capturing feature was a welcome addition.

My only complaints stem from 32bit compatibility and the abolishment of input managers: I miss multiclutch dearly, and now it is all but useless (unless I force everything to run 32bit executables).

As for the Exchange 2007 support, I’m having some weird-ass issues connecting to RIC’s Exchange server. It half-works, but on subsequent connection attempts the server rejects my password. I’ll have to give USS a call to make sure my settings are okay.

That’s about it.