Auto-save was not feasible for Illustrator until Illustrator was 64Bit in nature. CS6 is now 64Bit. It's my hope that in the future more changes will be made which were not possible in the 32Bit app.
There were scripts and other techniques to allow auto-saving for years. Therefore, it is clearly not true that auto-saving was not possible before AI was 64 bit. I continually wonder how After Effects and far more powerful software like 3ds max can have autosave for (15+ years in the case of Max) and poor little Illustrator does not. This is just another example of pathetically bad and user-unfriendly software programming by Adobe. I requested Auto-save at least 10 years ago to the Adobe wishlist. Still waiting. Every time I lose work I've done in Illustrator I internally bless Adobe for their great work.
Absolutely maddening. I'm sure I lose 10 to 20 hours a year, and I'm not alone; multiply that by the thousand+ people in my company that use Illustrator and you've got nearly half of a million dollars of wasted time, just within my company, purely because Adobe can't figure out how to incorporate an auto-save feature.
. . . and that's not even billable time.