Didn't you read my post? Both Oblivion and Fallout 3 had 2 years worth of development by themselves, if you don't count Oblivion's DLC, and about 4 years total. So no, it didn't have 4 years of development by the entire team. If you count development of TES V, then it was never developed by itself. But this is 2010 right now and we still have no TES V, meaning developing Fallout 3 and planning Fallout 4 has taken a huge toll on the development of TES V.
And for the record I thought Fallout 3 was absolutely amazing, and think Bethesda did a great job.
I did read your post and I failed to refer back to it in my post at all... Fallout 3 I did not feel gave me the openness and roleplaying ability that I get in Elder Scrolls. It was an FPS to me, no more.
On the production information, if Bethesda has been working on TESV since 2006 and we lack even an announcement... I am kind of disappointed. If they truly invested all of that work into Fallout 3, I feel like they wasted their time. If they have been working since 2006, the game should be amazing if released 2011/2012. If they have been working on it since 2008, then it should be amazing if released 2011/2012. A game won't be much better five years from start than three to four if you ask me. Look at Call Of Duty, popping out games from each company two years after the other.
Edit: Duke Nukem Forever... Just... It would have to be so freaking amazing at this point I would eat my shirt.