Ok- not exactly SP2 itself, but the Outlook Team has announced that the February update that shipped this week includes a number of performance tweaks and fixes that were originally destined for SP2. Notable among these tweaks are a number of improvements to PSTs, and the Fast Shutdown mechanism. I’m working on documentation for developers to take advantage of Fast Shutdown – look for that in this space soon.
Get the update here, and read about what’s in it here. BTW, if you don’t want to install a cumulative update, you can also wait for SP2 to ship, which should be here by April, according to the Office Sustained Engineering Blog. Enjoy!