I've been coming to the same conclusion that greydarrah expressed, although I haven't yet reached his virtual certaintly that the problem is caused by GPS use conflicts between apps. I do think it's the most likely, though.
I just went through all of the application descriptions on my system, and there are 37 location use apps on it. I'm listing them here just to see if we can find some commonality between users that are suffering from this problem. I suspect that since there are very few of us apparently affected, the app/s involved are probably one or more with small populations, but I'll list them all here.
My plan is to try to track which ones are active prior to opening Maps, with the hope that I can correlate them to try to home in on which apps are suspect, then look to remove, or at least stop them before opening Maps, and to track the results carefully. It's going to be messy. We need to keep in mind that there could be more than one app contributing to the problem with Maps.
My List:
Beautiful Widgets, Blockbuster
Catch, CBS News, Compass, Crackle
Earth, Evernote
Fandango, Firefox, Fox News
Googles, Google Search, Google Sky Map, Groupy (no ads)
IMDb Movies
Live Scores, Lookout
Maps, Mobile Banking, My Verizon
NFS Shift
Plume, Public Radio LiveStream
Shopper, Shopper - Shopping List, Smart Tools, Speedtest.net, Streetview
The Weather Channel, Tracker, TuneIn Radio
USA Today
Vignette, Vlingo, Voice Search
WRAL
I hope a few others sharing the problem will take the time and effort to compare results on their smartphones, and share their findings in this thread. We can really benefit from the effort.