So I'm trying to perform a clean install on my 160GB MBP. It's been erasing for about an hour. Does it usually take this long? I actually am trying to reinstall Snow Leopard after an upgrade to Lion. I didn't realize a really really important work program is PowerPC based so I need to go back to SL. Of course...it's Sunday and I need to have it all back in order by 9am tomorrow. Great.