gps satellites are not geosynchronous. they are designed this way so they will work if u are in a canyon, saddle, or depression. (basically a low area surrounded by higher land) they will come in and out of view/range but that is better then not coming into range at all.
proof here:
http://en.wikipedia.org/wiki/GPS
and here:
http://en.wikipedia.org/wiki/Medium_Earth_Orbit
this does tell your phone where to look for satellites, or more specifically, what satellites to look for. (what frequency to tune into).
there have been rumors that some people gpsone chip that is integrated into the msm7500 chip is bad. probably not true, but it has been rumored. more likely a software conflict with their oems.
if u interested in this stuff then download this zip file. I put in it all the pdfs i have read to get to this point.
here:
http://rapidshare.com/files/14317889..._pdfs.zip.html