Quote:I highly recommend you disable the background downloader (it's in the options, check it in your system tray). Running Bittorrent in any form while trying to game online will just drag your connection way down.
-Bolty
When it comes to Blizzard's version, much agreed. Most 'real' BT clients allow you to control the upload and download bandwidth you use so you do not choke your system. I don't see any such available options here, so it'll likely choose the highest possible upload it can.
Quote: it was stressing my DSL connection to the point that I kept dropping carrier lastnight. I died 3 times because of it.
This can and will cause the problems Concillian experienced above, even on higher bandwidth connections. Don't use it during regular or imporant play.
In contrast, the Guild Wars client only downloads new content in advance during the login screen and loading screens, not during regular play.