the iPhone 2.1 software update promises to give fewer dropped calls, but when even the announcement of such a fix does not claim to just make your phone work, but simply make it a little less unstable than it currently is, i am not very hopeful for getting a working phone out of that.
for me, living with a phone that drops the majority of incoming calls and requires me to hit redial a couple of times before i can call anybody is not all that bad. i am mainly using the data service anyway, and while that also has its issues, on average it at least seems to work better than the phone service.
finding out what exactly is going wrong would be really interesting, however. while the failure to simply connect calls looks like a network problem, on the other hand there seem to be many complaints in other countries as well, so maybe it is the iPhone after all? hard to tell, i guess, since probably many cellphone carriers use the same vendor for building their networks, so it might be just some incompatibility thing between the iPhone and that equipment?
the one thing i would really be interested in would be to see other 3G phones on the networks that don't work very well with the iPhone (such as AT&T), and see whether they have the same problems with connecting calls and using the data service. that could be a pretty interesting starting point to figure out who's to blame...