Lots of them are updated. I don’t care and neither should any Firefox user care about “lots of them”.
The only thing that matters to me with regard to this are the ones that I use and the only thing in this regard that should matter to all users of Firefox are which ones they use.
As of late Friday none of these which I use are compatible with Firefox 5.0 Beta 1. I checked them one by one at the Firefox Addon website.
Adblock Plus Popup
Beef Taco
Better Privacy
Cutyfox URL
Download Statusbar
E Tab 2 (FF 3.6+ & FF 4+)
Image Zoom
ReminderFox
SimilarWeb
TrackerBlock
Padlock
- one other I will not disclose
Total of 12 out of my 22 Extensions/Addons not compatible with Firefox 5.0 Beta 1 as of last Friday.
You must have better luck with LinkExtend than I do because my experience is that I have found it buggy and bloated. I have installed it and uninstalled it a number of times going back to Firefox 3.X and my conclusion is that it is just another junk toolbar. 