Windows Live Hotmail team blog, announced the upcoming version of M10 (milestone 10) of the Windows Live Hotmail (formerly Windows Live Mail, and former Kahuna) beta.  You’d to see the following updates M10:

• Re-branded as Windows Live Hotmail.
• Faster & More Reliable.
• Classic Version enhancements, includes: Spell Check, improved Photo Upload Control, and Bi-directional language support.
• Improved Safety Bar.
• Version Picker to choose between Classic or Full.
• More "forgiving" checkboxes.

The Hotmail Team rolls out Milestone updates in waves by server bays instead of all at once. So if you've not been updated, give it some time. You'll know you're updated once you see the "Windows Live Hotmail" branding in the header.

Windows Live Hotmail Blog

Microsoft, Window Live, Windows Live Hotmail, M10, Mail