I'm thinking something to do with network enhancements *and phones to utilize it* (dual core?).
CES phone exhibits seemed to be all about 4G this year, yet the company to bring the first "4G" network to the states doesn't bring anything major to the table. With the other carriers right on their coattails, sprints got to take it up a notch this year. I'd say they have something up their sleeves.
Lets see...
1) Introduction to market WiMax 2 (the 100+MB/s stuff) build out in 2011. Incorporate 20Mhz channels (doubling what the other companies are implementing) allowing for faster downloads and more throughput.
2) LTE & WiMax co-operate on same sprint & clear towers (this is something they've been suggesting going back to when everyone was saying wimax will die out and LTE will be dominant). Big $$ savings, and easier deployment.
3) Sprint to utilize some of the 800MHz spectrum currently dedicated to the iDEN network (nextel) for LTE/Wimax (2?) while simultaneously using the 1900/2500 spectrum bands. They are supposed to be phasing out the iDEN network by 2013, so at that point they will surely use it. From what I've read elsewhere, nextel is now under utilizing that spectrum band because of customer loss. It's an important spectrum because it penetrates buildings better than what they are currently using for Wimax (2.5Ghz); conversely the 2.5Ghz spectrum allows for higher data throughput. So, utilizing both (or really all three) bands would give sprint the best of both worlds.
4) A combination of 1 & 2 & 3 for something really fast and robust.
P.S.: Please sprint, don't tell us about these upgrades, then not give us a phone to use it with. USB dongles and modems, blah....