AnotherSomebody posted... That and Bizarre is kinda... not alive.
Activision acquired the rights for Geometry Wars alongside Bizarre Creations. So they could get any of their internal studios to make a 3DS version if they really wanted to. They probablydon't want to, but the chances of another Geometry Wars game didn't die with Bizarre.
As much as I would love another Geometry Wars, Bizarre is closed: http://www.eurogamer.net/articles/2011-02-18-bizarre-says-goodbye-with-farewell-video#cm-2156706
Unless another company wants to pick up the series, but if no one has yet, it isn't looking too good.
The problem with the DS version was mostly the slowdown caused by too many enemies on-screen. Of course, the 3DS should be able to handle that just fine, but that's more or less irrelevant now, anyway.