Here is a great chart on the capabilities of Windows 7 Media Center, XBMC and Boxee. I personally use Windows Media Center which is part of Windows 7 and I really like it alot. WMC spotted my Hauppauge TV Tuner and green button remote without any extra device drivers. Setup was easy with Cox Cable. XBMC is nice also, but it doesn’t support a tuner. It does get meta data including TV, movie and music pictures, data about your media, reviews, and even trailer links for the videos and music. See the chart below and checkout Lifehacker for the full review.

Hulu has blocked Boxee from accessing their content, but you can use this plug-in to get around that.
XBMC has already put together a quick plug-in to bring Hulu back to both XBMC and Boxee. A Team developer called d4rk at XBMC has created a plug-in to the Hulu plug-in which does some fancy decrypting to get Hulu working on Boxee and XBMC.

Hulu Plugin for XBMC [XBMC Community Forums]
How To View Hulu In Boxee [Boxee Forum]

Boxee provides you with an entertainment experience that allows you to hookup your computer to a laptop or connect to an HDTV, you can experience movies, TV shows, music and photos, as well as streaming content from websites like Hulu, Netflix, CBS, Comedy Central, Last.fm, and flickr.

Boxee would like to know if you would take their short survey to determine whether they should come out with a set top box as opposed to connecting a mac/windows/linux computer to your TV, or installing boxee on an Apple TV.