OverviewI purchased this Smartphone after 3 months of research. My criterion was that it had to play music via Bluetooth, had to have a windows mobile platform, and had to be comfortable. This phone satisfied all of them for the most part.There are a few cons to the phone, however; with the windows platform it will not be long until applications will come around to extend the functionality and fix problems. I'm a computer programmer and I'm currently working with the mobile platform to develop new programs with Visual Studio, hence the need for the windows platform. I can safely say that in the next couple of years we will be seeing some exciting new technology that will be developed with the new Smartphone and PDA's that run a platform like window mobile.The blackjack is an excellent device to introduce you into the Smartphone/PDA universe. With Blackjacks features for Email (3 different options to receive email w/ this phone), Instant Messaging, SMS/MMS, ActiveSync & MP3 player capability it's my opinion that the Blackjack is on par or surpasses any blackberry.Con Brief & Fixes1) Music plays on the speakerphone if you have no ear buds.First the music capabilities of the phone is excellent, however; if you do not want the entire world think that "you like big butts" when everyone hears your song "Baby got back" by Sir Mix-A-Lot coming from your Blackjack's speakerphone. I would suggest getting the wired ear buds or a stereo Bluetooth headset. After a little research I found out that if I wanted wireless music from my Blackjack I would have to have a Bluetooth headset that had a feature called Advanced Audio Distribution Profile (A2DP) and if I wanted to control the music from a Bluetooth device I would need Audio/Video Remote Control (AVRCP). The Blackjack has both capabilities so all I needed to do is to find a Bluetooth device with the same. I found two that are not big headsets: LG HBS-110 and Sony Ericsson Bluetooth HBH-DS970. I bought the LG HBS-110, I just bought it when I did this review so I can't tell you 411 on it yet but I can say that both devices WILL work with the Blackjack.2) The battery life of the phone is very poorCome to find out the new G3 network from Cingular takes a lot of power to maintain. For a music enthusiast, like myself, I am looking for longevity when it comes to my players batteries. So I did some searching and come across a small little hack with the Blackjack that will turn off that G3 feature so the batteries can last for up to TWO DAYS in normal use. Let me advise you now, if you do not know what you are doing when you are in the settings of the phone. You can seriously damage your saved data on your phone or even lose it completely. So, I advise that you get in, change what you need, and get out. Do not experiment unless you are willing to lose your phones data. On the main screen of the phone type the following: *#1546792*# the admin screen will appear, scroll down to selection "3 Network & Call Settings" and hit OK. Next, scroll down to selection"5 Network Mode" and hit OK. Next, scroll down until you see "GSM" with a black dot next to it. Then, push the soft touch button with the word "Done" on the screen associated to the button. Now exit the Admin Settings by hitting the Home button (the button with a picture of a house on it) and you're finished. In a few seconds you should see the icons on the top of the home screen change. Next to the signal bars you should see a picture of an antenna instead of G3. This little hack should extend the life of your batteries tremendously. Also, by changing the Network Mode you should NOT lose any functionality from the phone, the only change should be the speed at which you send and receive data on the network. If you do experience problems, reset the network mode back to "Auto" by repeating the above steps; then start your troubleshooting of the problem.