Some people are simply not happy unless they have SOMETHING to complain about. And in the event there is nothing to complain about, they will manufacture something to complain about. They will find some trivial little thing, like the lack of an email client, and then blow it waaaaaaaaay out of proportion.
At most, the lack of a preinstalled email client is a minor inconvenience. You just go and download one of literally DOZENS of options that exist out there. Thunderbird, Windows Mail Live, etc.
I do have to say though, that Thunderbird developers have really learned from Google's example, and utilized the power of search in the new version. If you have hundreds, or even thousands of emails, spread across multiple accounts, and you need to find some specific email... Thunderbird 3.0 makes that incredibly easy. I made travel plans for the holidays a couple months ago, and now instead of having to scroll through each message in an account, I can just type in a few key letters or words into the search bar, it gives me a bunch of results, and options for narrowing the search even more off to the side. Search results come up in a new tab, so it doesn't disrupt anything else I'm doing... Takes a little retraining, but the payoff is pretty big. It's also nice knowing that I could decide tomorrow to run out and get a Mac or install Linux, and I could use the same email client on either platform.