uTorrent 2.1 beta lets your preview video torrents while you download
If you're downloading a video file in the new version (say, an episode of your favorite TV series), the play icon between the status and seeds columns will go from white to green. As you'd expect, green means go. Once it's lit up, click and you can stream the video to either the Divx web player on uTorrent's server or to your preferred local player.
On my system, VLC worked nicely - KMplayer, however, wasn't too sure what to do and never started playing videos.
You'll find streaming in the uTorrent installer available for download here: http://download.utorrent.
If you're not ready to try the new beta, you can also download the somewhat more stable uTorrent 2.0 RC that was released yesterday. It doesn't support video streaming yet, but it does have one nifty new feature. You can enable a data transfer cap, which could come in handy if your internet service provider caps your monthly bandwidth.