.OST versus .PST?

Is the file format for an OST (offline cached mode) the same as a .PST?

Either way, the Outlook and Exchange combo is here to stay (which to be honest, is fine by me. Outlook does what I need in a corporate environment, and Outlook 2010 is particularly good IMHO).

The main question I have is "does the PST format have OTHER uses or is it highly email specific?".

Given that we are moving to "cloud apps" with "offline modes" (think Google Gears) I wonder if MS is positioning the PST format as a more generic offfline data store (as opposed to SQLlite used in Gears).

Dunno, just a thought.