I was having the same issues as a lot of other people - random websites wouldn't load, the wireless would disconnect, the router would time out and need to be manually reset, slow DL/UL speeds, etc, etc, etc. It has been one of the most frustrating routers that I have ever had in my entire life. I was about to return it until I saw that this firmware came out and I figured I'd give it one more shot. So I backed up my settings, installed the new firmware, loaded my saved settings....and...no help. I still had all the same problems.
So then tonight as I was getting ready to box it up and ship it back, I did a factory reset to erase all of my personal info in the router (paranoid, I know). Then it occured to me - I didn't do a factory reset after I installed the new firmware, I just loaded my old settings. So I figured I'd try one more time after doing a factory reset (post-firmware update), and this time instead of loading my old settings I went through the whole setup process again ....and.... FINALLY this thing works like it should! It's blazing fast, no problems with dropped connections or page timeouts, no random "oops!" pages, nada. It's been about 4 hours now which is the longest I have had this thing running properly since I got it 3 weeks ago.
So if you are having issues:
1. Do a factory reset
2. Install the new firmware
3. Do another factory reset
4. Walk through the entire setup from scratch again rather than loading your old settings.
This worked for me, hopefully it will for you too!