Just replaced my Bold 9700 with a 9900. I use the device in marginal reception areas a lot. I have found that the 9700 has much better service reception than the 9900. If I lay the 9900 down flat on a table for 10 minutes it will probably connect. The 9700 has no problem connecting but only shows 1 to 2 bars. Have BB changed the type of the antennae? Or the sensitivity of the antennae? Does the 3G\H+ require more power?
Did read somewhere that the Steel band around the phone has some effect! Also, some people have noticed an improvement with various OS, so your current OS may be having a negative effect too!
It is the metal band around the phone also. It's something for the radio's to have to work harder for. Okay there's some plastic but not a lot. I found when I am at home on my Torch 9800 I got -70dBm which is great for 3G but on the 9900 it's -77dBm. Odd...