I have been using a X2 since late November for the purpose of writing a review. On private basis, I have owned a X1 for over a year so I am quite used to the currently small range of Xperia phones. The X2 first impression was not very positive. That was mostly due to touchscreen input, or rahter the lack of response from user input. I would not have updated from X1 to X2 if I had to use my own money for this.
Sony Ericsson have now confirmed that the X2 firmware will have an updated in March. The Windows Mobile version number will be updated from 6.5.1 to 6.5.2. 
Some of the new features in the new firmware will include
- FM radio!
- Video telephony (unknow why this is mentioned)
- Faster GPS
- General bux fixes to improve speed and usability.
Another update will be released in May. X2 will be updated to 6.5.3. Xperia X2 hardware is not compatible with Windows Mobile 7
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