I was wondering who had that :-). We were originally going to go with d20.io but couldn't figure out if it sounded good or not, and so now that is our shortening URL instead. I checked before using roll20.net and nothing was set up on roll20.com, so we moved forward.
No need to justify it - you didn't do anything wrong. :-)
Contact me at troygoode AT gmail DOT com. Maybe I could trade the .com over to you for a domain you have laying around?