My battery sucks now, I lost power just before this thread was posted, why didn't it resume. I remembered that last time I run out of juice it resumed.
It is possible to manually disable the hibernation image which would allow OSX to resume in case you are running out of battery. Disabling hibernation mode is usually recommended for SSD users. Any chance you disabled it yourself? 🙂
My battery sucks now, I lost power just before this thread was posted, why didn't it resume. I remembered that last time I run out of juice it resumed.
Calibrate your battery to make sure your readings are accurate. Install iStat Pro to track your battery condition, among other things. This should answer most, if not all, of your battery questions:
Changing hibernation mode to 0 is most likely the reason for your Mac not going to sleep, I have it disabled as well (SSD) and mine doesn't go to sleep either. It simply shuts down when the battery is discharged, as described in the link I have posted above. Calibrating the battery will probably not help here, but re-enabling hibernation mode should fix it (or using the http://www.jinx.de/SmartSleep.html app). Then again, if your PC does have problems with hibernation mode it is of course better to leave it disabled. 🙂