I have no real desire to upgrade to Lion because I don't want my OS X getting any more ios-ish. But I do want to use iBooks Author. I think from my googling that this would work, but I just want a sanity check: I have an external drive connected that time machine backs up to. If I partition that drive, I should be able to install 10.7 on one partition and have it bootable and run iBooks Author there, while still using the other partition for backups, right? (The hard drive has tons of extra space, it's twice the size of my internal hard drive.) How big would the Lion partition need to be? And is thre any Wine-like way to do this without having to reboot to get in and out of Lion?