Since the OT is from 2008, thread-jacking doesn't apply - esp since one of the mods is in the thick of it. :p
Depending on the use-case, GMail is superior is several respects.
It has worked on smart-phones for years, and is a painless setup. No one who has maintained an Exchange implementation uses the word painless.
While there are ads, they are easily blocked, and I don't notice them if I am running on a non-streamlined browser.
GMail just works, and supports free-form multi-tagging, layered-multi-account rules, and cloud based storage and availability.
GMail has never eaten my InBox (outlook.pst file) and required a lost-mail restore. OuchLook ....."Not so much."
GMail has an open API and active developer community. In comparison, leading part of a 10M startup based right in WA developing an email encryption solution, we could never get access to the internal API of OuchLook. Even as a certified developer with insider friends.
I could go on, but especially now that GMail technology (including Postini) is available to small businesses for almost nothing, it is a superior choice in many use-cases where upfront and ongoing costs are important.
A small office can run a branded (their name) full collaboration suite for a year for less money (and far less maintenance head/heart-ache) than paying for one OuchLook license.
