I think lithium batteries will be great! PQ said their next drag cart will have lithium batteries. Probably, cart makers have not gone there yet, is because of the cost increase on the retail sell price on their carts, and in this economy they would be shooting their self in the foot. But you can bet they are ready to pull the trigger on this. The run time and maintenance would be so much better. Isn't lithium batteries what the car companies are using? Myself, I hate acid batteries, so when the time comes to be able to use lithium batteries, I will start the trips to the blood bank to raise the money to get my set.
Seriously, I am glad to see this coming, I just hope that most of the electronics are compatible.