Since a significant part of the blatantly off-topic questions on MO is from new users, one might consider displaying first questions from new users only once they have successfully passed the review queue. --
Do people think this would be a desirable change?
If yes, would it be feasible to do?
Edit: I think the answer by Francois G. Dorais and the comments by quid give valid
reasons why using the review queue for such premoderation might be not such a good idea.
Pre-moderation is a tempting idea but there are a few potential issues with it:
It's very unusual for a site like MathOverflow to introduce a delay before posting. Such barriers are likely to decrease site usage across the board.
It's not clear that pre-moderation is a sustainable model for a large volume site like MathOverflow. I am not aware of any comparable site that uses pre-moderation instead of post-moderation or simply no moderation.
On a more technical level, the review queue only requires two votes to clear or block while the main site requires five votes to close. If the review queue is used this way, then five votes will be needed which will increase the strain on the review system and decrease throughput.
There is also the issue of visibility and accountability. Since the review queue is hidden to low-reputation users and tucked away for all users, there would be essentially no accountability to such a system.