I have spent quite a bit of time dissecting this phone lately. The BlackBerry is certainly quite popular with some estimating its market share at 41% of all smart phones. On a recent trip to Pennsylvania, I saw many, many phones on planes and at the airports and I can certainly confirm that ratio. I counted close to 400 phones, half of which were some model of BlackBerry.
I have to admit, so far, this is the most impressive Java ME/CLDC capable phone found I have tried. Not only are many optional CLDC packages available but many more BlackBerry Java packages are present. That being said, Research in Motion (RIM), implements custom GUI packages that are specific to its platform. What that means is that if you code an application that follows the look and feel of a BlackBerry application, it will not function on any other phone.
I have to say however that this device is too expensive. At a suggested retail price upward of $400, it only features 64 MB of memory and an empty micro-SD card slot. A similarly priced iPhone comes with 128 MB of SDRAM and between 8 and 16 GB of flash memory. The iPhone screen supports touch and it's twice the vertical size of the Curve's screen.
RIM also develops probably one of the worst integrated development environments (IDE) you've ever seen. The JIDE is an all Java IDE that you use to code for the BlackBerry device. JIDE redefines what the word "ugly" means. Fortunately, RIM has started to develop a plugin for Eclipse and a plugin for Visual Studio. It's also possible to use NetBeans if you have enough energy to invest into it.
Looking at the BlackBerry, I have to wonder if the company suffers too much from the "not invented here" mentality and how much of that affects the price tag of its products. The company develops an IDE, customizes the licensed library and CLDC virtual machine from Sun, has its own executable format, implements its own content designers tools, etc, etc, all of which are very expensive. Talking to various colleagues these last few months, I am convinced that RIM must refresh its hardware in order to stay competitive. By refresh, I not only mean the power and visual appeal of their devices but the overall quality of the BlackBerry development platform or risk irrelevance.