When you go into recovery, the first the HBoot checks for is a valid PC36IMG.zip file (stock ROM). That is the "update" that it finds each time.
so does this "update" wipe my phone?
If you are stock (not rooted) you could run this update, but you won't have any advantages. When you download the OTA, it is writing the PC36IMG.zip file to the root of your SD card and then running a script to install it. Because it should match your current setup, it shouldn't wipe anything.
Are you trying to do something in particular or just looking for some information?
no i'm not. just noticed it asked to update when i went into recovery and when i did it updated but i had to do my set up (email) all over again
