Dead battery and oil life question

[Hal]

I'm getting ready to go in for my second battery replacement and by the way, I don't have any accessories plugged in that could cause a mystery voltage draw, I'm even anal to the point where I always turn off the radio and climate control before turning off the ignition. I know this topic has been visited a lot but has it ever been resolved?
on to my real question...
When the battery dies and gets removed and replaced what happens to the almighty oil life sensor algorithm thingy? Does it just reset and think you had an oil change too? if so, some folks could have some nasty oil and the computer would never know it. I change mine based on mileage (yes I'm one of those dorks). But what do you think about the computer/oil/battery thing? (F5..)