Currently, I don't plan to release the framework elsewhere. I had some vague plans to release it on Play Store, but there are some reasons for me not to do it:
a) The rudeness in comments and ratings is unacceptable. This isn't for single apps, it's the overall feeling I have. I spend much time on Xposed and everything around, I don't want someone to insult me for it.
b) Limited supporting capabilities. I think you can reply to comments now, but a dialog with the affected user would be required to fix bugs that may occur.
c) Unexperienced users. In the best case, you just need to install the Xposed Installer, click the button, install a module and activate it. Restart and you're done. But problems do occur, sometimes resulting in bootloops. I hope that most users here will be able to make their phone boot again (if only by restoring a nandroid backup). I don't expect that from the average Android user, even if the description says "ROOT" and "BE CAREFUL!!!". I recommend these users stay off from risky modifications like this one.
d) When somebody writes a module and publishes on the Play Store as well, their users might have trouble using it. Then these users will need to communicate with the developer of the module, but they might also contact me directly. Or if the developer doesn't know the answer, he might contact me. I would have to expect more support requests on different channels. More time spent on support => less time for private life and coding => less fun.
e) Not sure what Google thinks about apps which interfere on such a deep level with their baby.

Regarding license.. yeah, probably I should think about this. Tungstwenty has also helped with the development, so he should also have a say. Considering that many parts of Android are under the Apache License, Version 2.0, it would probably have to be this one or a compatible license.
Tired of updating your mod for every new ROM release?
You want give users the possibility to combine different mods without creating tons of different files for all possible combinations?
Then have a look at my Xposed framework - modifications without APK changes!