I'm digging this new edition of Firefox. Not just because it feels better, as far as speed goes. But the features replace and fix what has been wrong with Firefox for the longest time. And I don't mind saying I absolutely hate standard Firefox. You can open that thing and let it sit idly by and watch it get bloated for nothing. Even a brand new stripped down installation. It looks as though the Developer Edition operates similar to Chrome. Running numerous smaller processes separately, which would run far more efficiently.
But there's a snag that cannot be ignored here. I also notice that even when you close tabs, processes are still running in the background. For instance, when I go to a Youtube video and let it begin to buffer, then close the tab. Firefox is still using the bandwidth of my data connection. Even though I closed the tab. I go into Task Manager (Windows 7) and start killing firefox.exe processes and notice it lets go of my data. Of course, it also shows a message in the browser that my tabs crashed. So the browser is holding these processes after the tabs are closed. I don't dig that at all.
Where I come from, if I close a tab, I want it DEAD. PERIOD. If I click the BACK button while a page is loading, I want that page DESTROYED QUICKLY and go BACK. When I tell Firefox to STOP, I want it to STOP EVERYTHING. I have yet to find a browser that will do that.