Mail.app doesn't detect address in address book
Which field is the name "Blast Corporation" in your address book? Supposedly by default Mail only auto-completes addresses that have been used before through Mail. I'm not sure if that is exactly true though, since I just now setup a contact in my address book which I've never used in mail and it auto-completed the company name. It's possible that you need to check a few settings in Mail.app preferences:






Here's another example of a company in my address book, which auto-completes in Mail.app