Hey the Smith 610 will work with 40 S+w (or 10mm) sadly I hear it has recently fallen by the wayside, however it's still around on the secondary market and could be one work around to the problem if someone really wanted to carry a 40 cal revolver --- BTW I'm sorry I ever sold mone loved it --- it's an n-frame and very fast with moon-clip reloads.
So far as the old guard and wheel guns, I used to live in Phily and vist NYC freqently and threre were a lot of revolvers still out there, I suspect many, having an intrest in guns forget that to the officer who carries everyday, the wepon just represents one more tool he needs, and untill proven inferior, he or she is unlikely to change, especally on departments where that change comes out of their pocket, as is the case in NYC and may other places.
So far as gorernment contracts --- whay do you want -- they try and distill down what they need, yeah sometimes it's awful specific but atliest if someone else wanted to try and meet that spec they could, if it's brand specific then it procludes that ever hapening, plus the specificity needs to be there becuse of all the companies and suppliers that love to screw the government --- take it from someone who has been mighty screwed at times it does happen very frequently on little BS things that eat away at a budget and cause massive frustration and heartache.