I don't use hotmail that much, but I am a big fan of GMail. My company uses Google Apps for your Domain, and my personal email uses the regular Gmail service.
I used to use Outlook 2007 to get my work email, but now I just have Google Chrome open all day, first tab is personal email, second tab is work email. Stable, fast and sweeeet ....
I thought that this upgrade to Hotmails interface would bring it on par with Gmail, but it doesn't. Not by far. The banner on top is so, so big and ugly. Ruins the whole interface. I like that Hotmail works in Google Chrome though ... that's good.