The Blackberry Bold is a great phone on paper and appears to be the best Blackberry to date. But after having used this phone for the 8 months it's been available on AT&T I would have to say that this is one of the worst phones I have ever used.
Feature-wise it is great. The screen is awesome, the physical keyboard is perhaps the best among smartphones, and it has a very loud speakerphone. It is also world-roaming capable, has a camera with flash, accepts Micro SD, takes video, and has a very nice email feature.
But here are the problems that I have had: random rebooting (~5 mins each time to reboot), extremely fragile case and lcd screen (I'm on my second unit and this one is broken now too), "call failed" errors, low memory warnings (the phone will begin to delete your data without asking when memory is low), a keyboard that would not register the key typed but another random letter.
General issues with phone: very slow internet browser (check youtube for a demo, it is embarrassingly slow), unstable operating system (random freezes and java error messages), short battery (it will not last an entire day of 'normal use), once radio is off from no battery it will not make calls or receive data until it has been charged for 10-15 mins.
I don't hate Blackberry, in fact, in many ways I still like it. But some of the things I have experienced with this phone have been extremely annoying and reduce my productivity. Random reboots are very annoying when you need to make a call, say for a meeting, and your phone is in the middle of a 5 minute reboot cycle. Or you know that you are in a spot with good reception yet your Bold refuses to cooperate and gives you multiple "Call Failed" messages, also annoying when you must make a call. Low memory messages are a daily thing now, and the Bold handles this by deleting your stuff - having emails deleted is normal now. I once saw my phone have the low memory error, then reboot, then my wallpaper was changed to the default one - surprising. For about a month, the keyboard would not work correctly. If I typed the letter A, an O or U would appear; this happened for about 1/3 of the keys. My friends thought it was funny, but because of the keyboard input problem, I could not even unlock my phone. For some reason, after about one month, it magically fixed itself and started working, very strange.
I'm not going to complain about the phone being fragile because it was me who damaged it, but I will say that it is almost ridiculously fragile. I don't throw around my phones my any means, but a cracked lcd from light pressure that any other phone could handle and a cracked frame without ever having dropped the phone is unreasonable. By the way, the cracked frame now makes the battery cover latch loose and the rear cover sometimes comes off.
I've tried to give Blackberry many chances. I've even spent many hours wiping and reinstalling the OS and reading forums about how to fix my issues. But I just don't have the time to always be fixing my phone, and the biggest reason, it is more of an annoyance than a benefit.