So each time the 3GPP tries to come to terms with creating a new generation of Wireless Standards to draw the networks more towards a truly unified single spectrum, something or the other (read AT&T) goes ahead and tries to ratify new "bands" for that particular deployment.
How much more fragmentation is there.. I mean seriously. With GSM: it was 1900 Mhz in the USA where elsewhere it was 900 and 1800 (primarily 900 for range and the 1800 was used for data and backhaul). Then we wisened up a little and got 2.5G but still primarily on 1900 MHz. Then the Big T did the only smart thing in their history. 850Mhz. Decent range. Thats what happened to 3G. 850/1900. Then T-Mo got their own AWS band. So now phones need to support 850/900/1700/1900/2100 for 3G. The first pentaband phone was the galaxy nexus (yes Nokia N8 was there but it doesnt count).
Now with 4G. already we see 700 Mhz (Verizon and AT&T). Then we'll most likely see more deployment by AT&T and T-Mo on the AWS spectrum. Now there is a 2.3 Ghz band for more LTE. The entire approach is so screwed up. Am i supposed to carry one phone for when Im in the sticks as opposed to another when Im on the road and then another when im at home?
Here's the issue everyone wants there to be dozens of carrier in the us all of which are suppose to have nationwide 4G and unlimited. Now between 700 MHz and 899 MHz is a total of 200 MHz. There is no way that is enough for a dozen nationwide carriers to use on 4G. Even with just 5 carriers that would be only 40 MHz each and some of that would have to used for guard bands.