1. Software updates are not performed routinely, it can take quite some time to do all of them. Software may get updated at service time depending on the dealer or what the fix is, you'd need to ask the dealer specifically when booking the car in if they do this or not.
2. No way to tell without a Tech-2 unit and the workshop data to see what updates there are, with tis2web updates are downloaded directly from SAAB and can be updated at any time (as I understand it, I've never used tis2web).
3. Fixes for various problems, possibly a slight improvement in the way your car runs, most likely nothing stunning. Some of the improvements for the 1.9 diesels (and by extension other cars) can avoid problems in the future, especially problems related to the emissions control.
If you do go for the £10 updates, ask them very clearly if they update *every* unit, if they only do engine and gearbox it's not such a great bargain as if they update everything that can be updated. I'd ask them if they do it if they can tell you which units they updated even if it costs a few quid more. For £10 it's probably worth doing as the benefits will be more than a tenner if they do help you, if not you've only spent £10 so it's no great loss.
