There aint no free lunch.
I can't imagine the magnitude of storage that will be available say 10 years from now!
Considering how much the prices of storage have fallen right now 1 gig ain't a big deal. But it's going to be huge because they are doing something no one has done before - something unique. It will force Yahoo and Hotmail to also increase storage.
They say that we'll be able to search through any email we've EVER sent / received. Does this mean that we'll not be able to PERMANENTLY delete any message? It might show the message to be deleted but will it be stored on the google servers?
I doubt it. It would make NO sense it they did that. Believe me, people will find ways to make a gig of storage look real small. They have to allow for deleting permanently.