People still dig SR2 just SR4 is out and so of course a lot of people are enjoying it and with all the DLCs coming and such. Once that is all out then the SDK comes out for SR2 I'm sure it will breath in new life. I think they are also still seeking the Source code for the game?
Even IdolNinja plans to return to modding SR2. Once he has his fill with SR4. I believe we may get a GotR 2.0 depending on how the SDK shapes if it will be needed in it's current form of GotR or become something else.
I don't know if this will still be true once the SDK is out and if the source code is found but I heard a lot of SR2 tweaks are locked in the .EXE which is encrypted by DRM. So if it's at all possible to get the game released DRM free at like GOG.com I believe it's still unknown though. If it did I'd hope it would get released as a GotR edition.
The future of SR2 seems bright just no ETA on this stuff. I'd assume we're gonna all kinds of cool stuff for SR2,3 & 4.
As far as modders go for SR2.... I recall this one Modder that had some cool stuff but him and IdolNinja got in a dispute and the Modder was banned for using others work without permission then going off the handle. It would be cool if things could be resolved as he did seem to show some cool progress but that's between him and IdolNinja.
Anyways well just have to wait for the SDK to come out. As for a date.... I'd assume when the DLC wraps up for SR4.
GotR does have a lot of cool stuff from other people who did mod SR2. There is a few stuff in the mod release section and a few in progress. It more than likely will pick up again.