lets see if i understand this. they are going to force us to upgrade ? i just got my new dx6i not 3 months ago or so. and now will have no choice but to upgrade
That's jumping to a lot of conclusions all at once. As TechDiver said, you do not need to upgrade. In fact, YOU NEVER have to upgrade. IN FACT, they are even suggesting that most people SHOULD NOT upgrade. That's right, read any of the Spektrum pages regarding DSMX and they keep saying it solves a problem MOIST PEOPLE DON'T HAVE. And as such, most people do not need to upgrade.
The DSMX transmitters and Receivers are fully backward compatible meaning you can buy a DXMS transmitter and only fly DSM2 receivers. AND you can buy DSMX receivers but never buy a DSMX transmitter, stick with a up till now current DX6i or DX7.
As near as I can tell, DSMX is exactly the same as DSM2. The only difference is that in DSM2, the TX and RX choose two open channels and stick with them no matter what. While in DSMX, during link negotiation, if both TX and RX support DMSX, then they agree to frequency hop. That is, they choose two open channels and keep changing them so that if anything ever happens to a channel or two (interference, or a misbehaving radio jumping on an occupied channel) then you are never affected because they TX and RX just hop away to a nice channel.