If you're not playing Cro-magnon Rally all day, the battery life after the upgrade is vastly improved. I charged it sunday morning, used it pretty often during they day with push notifications, location services, and 3G on. That would previously have left me with a 20% charge late in the day. When I go up this morning, there was still better than a 50% charge. To me this is bigger than even the stability improvements. Additionally, 3G seems a lot more consistent, I haven't seen an app crash, apps install very fast (unless it is a big download), no more sluggish contacts. It's good to see they focused on the most important things first. Now that the foundational stuff is solid, I think we'll now start seeing some sought-after features appear.