I wonder why emails can still be accessed through an email client? I didn't try it when it was down but I would think that all of your data is stored on a server, and if Gmail can't access it then nothing else should be able to access it.
That won't really make that much of a difference though, because my account was not able to receive any emails during that period. Gmail came back online for me last night and I just got all of the emails from yesterday this morning.
