Want to Add "Xbox LIVE Tester" to Your Resume? Microsoft Wants to Oblige You
According to a blog post by Larry “Major Nelson” Hryb, the interest in beta testing was sufficient back in July’s first round that another round was warranted, and although they’re accepting “for more” testers this time, space is limited--so you better get on it if you want in.
Voice search is coming in certain areas
Beta testers will get an update in a few days, after which time they’ll be able to check out new features including Internet Explorer for Xbox, voice search, and miscellaneous tweaks such as recommendations, ratings, pinning, favorites, category search, and discovery features. Interested parties can head here and sign up with your Live account.

Image credit: The Verge
“Xbox LIVE update beta tester”; that probably works as a pickup line somewhere.