Sony's been working on new and improved batteries, ones that use olivine-type lithium iron phosphate as the cathode material. They say that these fancy new batteries offer up four times the life of current lithium ion batteries and charge up in a mere 30 minutes.
Sounds awesome! Unfortunately, the new batteries are only available in power tools at the moment, but they'll phase over to consumer electronics "gradually." Well, something to look forward to I suppose.