IMHO, a merge would be fine.
*The general and Q/A sections (DZ doesn't have a Q/A section?!) can be merged. It's pretty common practice to say what kind of phone, what ROM, etc that you're using anyway. If they poster doesn't say it, someone asks them, so I do not see that being a problem. Merge them.
*On the outside, these phones are identical. Accessories can be completely merged with no issues. Cases that work for DZ will work for G2 and vice versa.
*For the Dev section...well:
http://xdaforums.com/showthread.php?t=857390
A thread in DZ that has a root method that works on G2
If something doesn't work on both phones, then it's not big deal to add the words "G2 ONLY" or "DZ ONLY" to the title so people don't try the wrong things on accident. If someone doesn't read the whole title, then they're stupid and deserve the consequences.
*Themes and Apps
Same reasoning as the dev section
A full merge is the best idea, then we'll have everyone on the same page as these are basically the same phone. I can't see a reason why we shouldn't that can't be fixed with simple logic.
@Garcia
Got that screenie for ya, it's attached. You can even see the
www.xda-developers.com at the top with no added address paths