Is DarkTor the definite name? The word Tor is becoming a little synonymous with drugs and child porn. VPN and others not so much.
I think
DarkCoin + DarkTor + Dark... - good names to get lots of free PR (or black-PR - doesn't matter)...
When Darkcoin MarketCap will be > $1.000.000.000 - may be it'll be time for some rebranding - but it will be another story...