I have read somewhere a thread from pizzasgood from the developer forum, that BarryK is implementing a change so that saves will only be made at shutdown to reduce this problem even further so - 25>>>>yrs.....This means that with normal use i.e. 6 hours a day 10% write rate (36 minutes of writing) it will last approx 25 years!!!.....
I don't think the battery will keep up, though
Aitch