It's been a long time since either FO or PS:T were released, so holding people to those standards may not be realistic simply due to the passage of time. Styles, inlfuences, theories etc change, so whatever Obsidian come up with now may very well likely not mirror either FO or PS:T.
I don't think comparing BIS and Obsidian is fair, either. While Obsidian clearly has a lot of BIS people, it's not the same group and may not even have the same agenda (there are some key people missing). I think comparisons may only be valid after we have a couple of Obsidian games to play.
Expectations are inescapably high for Obsidian, and justifiably so. There's some good talent there, and a desire on our part to see some really good (eg PS:T or FO) RPGs made for the PC.