[kyrra]

My guess: data for their Apps customers are backed by completely different set of servers/infrastructure. This probably allows them to tell large potential customers that if GMail proper is ever hacked, their data would be safe (as it's part of some different system). It may also give them extra time to pen test new systems to make sure it isn't hackable before deploying it to the people that do trust it with their company's email.

[jakebasile]

That's feasible. It still strikes me as odd that even if Apps Gmail is indeed on different infrastructure that it would have a completely different API. All other Gmail clients (web,app,etc) work on Apps Gmail, in addition to vanilla IMAP.

I'd feel a lot better if they'd just explain what the hold up was, or if they don't plan on expanding to Apps customers. I'd be disappointed but at least I wouldn't be completely in the dark.

[kuschku]

Apps Gmail is different, cause you can even get it self-hosted. Several larger companies actually use it self-hosted in-house without running it through google.