There are lots of people reporting on the spotty iPhone 3G reception issues and according to Barron's it looks like the BlackBerry Bold may be experiencing those same 3G reception issues. The Bold is available only in a couple countries at the moment and isn't yet available here in the U.S. so there is the possibility that the Bold's software will be updated prior to the release.
According to the Citigroup analyst, the Bold does have an amazing display and updated BlackBerry software that adds HTML email and a better web browser. But the 4.5 software update (the Bold runs version 4.6) is available for some current devices and will be widely released for other devices and adds the HTML email, better browser, and video recording capability so there may not be a compelling reason to upgrade. I use my EDGE-enabled BlackBerry Curve and the Opera Mini browser and new BB 4.5 browser works quite well without 3G. In truth, I hardly notice that 3G is not supported on the device since email also seems very snappy. I tested the Sprint BlackBerry Curve and am not sold that 3G data is a compelling feature on a BlackBerry. 3G is a vital feature for phone calls though since you can answer a call even if you have an active data connection.
I haven't seen a definite release date for the BlackBerry Curve on the AT&T network and the reported issues with the 3G radio may be delaying the release. There were reports that the Infineon chip was a possible cause of the problem. My search results indicate the BlackBerry Bold uses the Marvell Tavor platform for 3G so the problem with the iPhone may be on the software side, which means it can be fixed by Apple.
If you are looking for solid 3G reception you may want to consider a Nokia S60 or Windows Mobile device for now since their devices have been performing well on 3G networks.