Best guess on release for 3.2 is sometime in late August. The background patch download currently in use is an attempt to address the question of long download times; rather than keeping the whole thing until it's all done, they're taking the parts of the patch that test out well and attempting to "frontload" them into as many systems as possible, using a peer-to-peer (p2p) network based on the existing Blizzard Downloader software. As such, the background download will never actually be complete until Patch Day. However, when the final patch is released, you'll already have some of it waiting on your hard drive; your computer will just need to download the parts you don't have, then install the whole thing, which should go much more quickly.
I have heard reports that the patch will also include sidecars for the cycles - can't wait to see some dwarven paladin cruising the mean streets of Ironforge on his Mekgineer's Chopper, his faithful night-elf rogue companion in the sidecar, a Jeeves robot mounted behind serving as their mobile shop and bank...
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.