Personally, I don´t think they are biased. They are disappointed in the fact that another addition to series has only driven it further from the original vision. To be biased they should have a preference to the older games without objectivity. The points they make about fallout3 are legitimate and well-reflected, and certainly not formed from the basis of the old game. A running joke trolls use on their forums is that NMA-members don´t like fallout3 ´cause of it not being 2d-isometric. Could not be further from the truth. Many people looked forward to the game after viewing screenshots and short tech-demo´s. What people did not like was the shallowness. Dumbed down subject-matter. Little, to no, dialogue. No character customization.. etc. But they are quick to mention that it can be enjoyable, and it is certainly the best game bethesda has released in a while. It just isn,t fallout. I like to think of it as a spinoff: Fallout Battles, the Capital wasteland 
The review on NMA is, in my opinion, the best review for fallout 3. In short, it is far from a deep experience on pair with the originals, but is occasionally fun to play.
It is a good site for the integrity of the fallout universe, and for rpg´s in general. Let´s just hope there will be a resurrection of the genre now that Interplay is back on their feet. If the get the old Black Isle and Troika gamestudios in their staff, we should see some pretty awesome games 
