Windows Live Hotmail, a completely rebuilt web based mail client set to replace MSN Hotmail, started its rollout to selected markets this week. This morning, I talked on the phone with two members of the Windows Live Hotmail team from their offices in Mountain View, California. Omar Shahine and Ellie Powers-Boyle have been working on "Kahuna" since 2004, and we talked about the code base, the beta, performance, and more.