I have to ask this only because I used to suffer the same issue. When you applied the update was your battery full? If not this could be the issue. I can tell you how to wipe the battery stats and start fresh but it isn't easy unless you are rooted and have root explorer are are familiar with adb during recovery. This is why with any flash or update you should always have your battery fully charged. Many have said you tube looks much better and it is rumored that the drivers in the 2.2 kernel are updated for the chipset. Also why Some say angry birds looks great now without adding gl drivers. EV and 3G are just .png changes. Android uses 3G for most carriers but Sprint uses EVDO. I really think Sprint let this go with less invasion to allow the more vanilla experience. I think google wants you to use GPS assist if I am not mistaken. Try checking that and see what you get under location in the menu. Please post back if this fixes it. I can add it to the primary post for info if others have the same issue.
Samsung Epic EB13 Deodexed with Genocide Kernel
Samsung Moment DL05 Froyo Port Rooted with MRWRX Kernel 2.0.1 Recovery 3.1.1 and UD4.1
Samsung Intercept (Sprintercept) 2.2
For all your rooting needs. http://www.sdx-developers.com/