Lots of people have been pointing out the activity of their background downloader. Yesterday Zarhym announced that the download would startup soon, delivering the first part of the 3.0.1 content patch.
The downloader is running along for many of us – both the North American and European versions. The patch files it is downloading are between 821 and 992 megs. Be sure to let it run only overnight if you don't want any problems while you run your groups or raids.
To exit the downloader, Windows users can click the Blizzard icon near the clock on the taskbar and choose "Cancel" when the window appears. Macintosh users can go to the file menu and choose "Quit" when the downloader application is in the foreground. The download will restart the next time you launch WoW.
Patch 3.0.1 will bring about a ton of changes in preparation for Wrath of the Lich King. There is no announced release date yet for WotLK, nor is there a date for when 3.0.1 will go onto the live realms. However most people expect 3.0.1 to hit the live realms in a month or so, and Wrath to be released in early November. Some of the major highlights of 3.0.1 include: