I was banned yesterday also (after 2 days of modding). Seems to be a CID ban, and I did use the CID changer (all 0's). This was my set-up:
1) Destiny back-up (obtained from the Internet)
2) DLC pkg installed (had both the Frontier and the Intrusion Ghost shells, but didn't equip them prior to the ban)
3) Used the RTM took consistently, in Raids and Strikes (but only in PvE, not PvP) -> defeated Atheon in about 2 seconds
* On the day of the ban, I got randomly disconnected from the game world (error code: baboon), after which it took about 10 seconds to connect to the Destiny servers.
Tried logging in on a different account, and still get the banned message. Gonna purchase some more private CIDs. Bungie thinks they're clever banning indescriminately; they are silly in thinking that they can keep CFW users out. I am against PvP modding (WTF is the point of that?), but having fun with friends while modding is a different story.
An example of merely having fun: a few days ago, while in the Gorgon maze, I enabled the damage multiplier (and it applied to ALL 6 of us, which I found strange) and we ended up running through the maze and killing every Gorgon in our path. The "Gorgons grow stronger" message must have popped up about 30 times. I was laughing throughout the entire experience. Bungie is just angering CFW users, and when an actual anti-ban is released they will mod the game mercilessly.
Just my 2 cents folks. I enjoyed playing the game, and am disappointed that I was banned since I just bought my first Exotic piece of armour using the 13 Strange Coins that I had acquired. On the bright side, I only started playing the game about a week or so ago so I didn't lose much.