Reproducable via autosave, by any chance?

Also, if you keep getting freezes, could you try updating your video drivers? It dosent seem like it's relates, but it's one of those things what we like to weed out early.

Same here. 

http://dl.dropbox.com/u/5475789/debug2.err

Reproducable from this save:

http://dl.dropbox.com/u/5475789/testmarketcrash.EleSav

http://dl.dropbox.com/u/5475789/DxDiag32bit.txt

http://dl.dropbox.com/u/5475789/DxDiag64bit.txt

It seems to be dependent on where the market is placed.  It occurs when placing market in city Fire (middle section of my lands, to the right of where that save opens), in Fire's uppermost right area, up against the mountains.  It didn't occur when placing the market in the mid-south part of that same city (and after this successful market placement I tried in the upper-right part of city "Fire" and it froze).  It also didn't freeze when placing a market in the city "Air".

Video drivers are 8.17.11.9621, most recent are 8.17.11.9745.  I was going to hold off updating but will and report back.

I also encountered this hang.  I attempted to build the merchant in the most SW corner of the main city.  I was unable to reproduce the crash from my last save, though it was a few turns back from the hang.

debug.err