PPM and FM are the same thing. 2.4 is coming on strong; however, the old frequencies will likely be in use for quite some time. My guess is PCM (which is a part of the old 50 frequencies) will eventually go with the old 50 frequencies. If you have the 72 Mhz stuff, and your club seems to be able to control their use, I would not jump, just because the new stuff is available. For one, your old 72 Mhz is selling for peanuts on Ebay, and is worth more then it is selling for, because of the 2.4 ghz. This means there are fantastic deals on very usible equipment out there and it is a great time to get started in the sport. If I were a beginner, and didn't know if I was going to stay with the sport, there would be no reason to do anything other then buy 72 mhz equipment.