I checked out the Honda/Acura "Maintenance Minder" info on their website. The demo video mentioned that the following conditions are used to calculated oil change intervals:
Higher Engine Temperature Operation Duration (length of time in condition -- such as extreme heat and loads)
Low Engine Temps: Drip Distance and Time (short trips shorten the interval)
Total number of miles driven
Time since last change
Of course the last 2 are obvious, but I wonder if it starts out at 7500 miles under "ideal" conditions, and if the time portion just reminds you if it's been 12-months since the last change (as per the manual)
I was surprised that they delved into engine temps as the primary variable, as the average owner probably doesn't care.
Acutally the engine temps(oil temps) is probably one of the more important aspects of the oil change interval. If the oil temp doesn't get hot enough to evaporate the condensation that forms while it's sitting the interval comes way down. That why OCI is so much less for frequent trips of less than 10 miles, cold environments, etc.