Posted this in the NON Verizon forum as an answer to someone's question, but I thought it would be of help here:
I have had 3 different Gnex's, each with new SIM cards, each new out of the box, and I made sure the verizon store rep gave me phones widely separated in serial number. I live in a non-4G area, and the coverage is SOLID, SOLID RED on the map. NO weak spots. My Droid X, sitting right beside my Nexus, gets -77dbm signal while my GNex gets -96dbm. Insides several stores, and in some parts of my house, I get -120dbm where my Droid X gets -89dbm. At work, wher my X gets -77dbm, I'm at -93dbm on the GNex. My first phone missed calls (went straight to voicemail) even though I had 2 bars (a strong signal at my house). My second phone froze and dropped into repeated bootloops that only pulling the battery solved. This third one has the EXACT same reception problem, flashing the 4.04 radios and Rooting and Installing the Franco Kernal and Axiom Crossbreed does seemed to have stabilized the signal minutely. I really don't think this is a bad individual phone. I believe there is a firmware or hardware issue here. I am set at CDMA only since I don't have 4G. My data connection virtually never drops....it's VOICE, and getting the phone to RING in areas of "low signal" that's the problem.
My calls are always VERY clear, and I've not had much issue with dropped calls at all, certainly no more than with my Droid X.
I'm not sure if my dbm reading is the 3G signal or the CDMA signal, but I can tell you that I LOVE this phone, I'm in the last third of my 14 day period, and I'm working hard to decide if I'm going to keep it or if I'm going to the Razer Maxx, which is currently backordered until after my 14 days is over, but which gets -77dbm here at work where I get -97dbm. Reception by my wife's *cough* iPhone is comparable to the Razr and Droid X.
I haven't heard whether 4.05 will address the CDMA signal strength or not.....all I hear is LTE discussions. I'd hope it would, but you never can tell.........