I was able to download and install Lion on my 3-yr-old MB Pro--took nearly 5 hrs, but I got there. Mail is a bit strange--sort of like on my iPad. Ditched my incompatible programs, downloaded & installed a new Solitaire and am waiting for the new Across Lite to come out sometime today. Going on the road, for which I take this MB Air, so I figured I'd buy another copy of Lion for it so it'd download overnight and I'll be good to go. I got to the App Store and the Lion download page, and clicked Download and then Buy. I got a popup box informing me I'd already bought and paid for it, and a button asking me if I wanted to download it again for free. (I thought this was odd--$30 gets you more than one license?). Clicked OK, nothing happened, clicked Buy again and the little Lion icon jumped into the Dock, with the comment "Downloading" and the green Buy button on the App Store page turned into a white Installing button. But this time, it's been 2 hrs and there's no blue at all in the Lion icon's progress bar. I just got an e-mail telling me PayPal has issued me a $30 refund from the App Store. Is that why I can't download to this MB Air? Should I abort, try again and then click "Cancel" when I get the dialogue box?