How long is Li-Battery good for?

In the long run, I would recommend Lithium ion batteries, because in theory, lithium ion batteries last forever, if they are manufactured correctly. Most rechargeable batteries, though they claim they last forever usually last for about 500-1000 charges before starting to go dead. Also, Lithium ion batteries hold a significantly higher charge in most cases. The problem is, buying spare batteries for a lithium camera are much more expensive than buying rechargeable AA batteries, $50-60 versus $10-20. Also, if you're traveling, and either lose your battery, charger, or just run out of battery charge and don't have time to charge the battery, no matter where you are, you can probably stop by any local store and pick up AA batteries (even in Africa, I've done it), but if you run out of lithium ion battery charge, no more pictures.