According to Reuters, Microsoft has sold over two million licenses of Windows Phone 7 handset manufacturers like HTC, Samsung or LG. I think that all these licenses are not active, but will be in the not too distant future.
Also commented that Microsoft has recently reached an agreement with the manufacturer Nokia to develop a product line with this operating system and set aside the old Symbian.
The reasons for not yet developed the application on Windows Phone 7 I think that depart from reality. I read in forums that one of the reasons is the low number of devices with this operating system ... I think it is unfounded.
Another reason is that the API does not allow them to read the numbers of contacts of the device ... There are alternatives, such as manual entry or import from Windows Live, Facebook, etc.
Please heed to this request and that refer to your software is cross platform, WhatsApp realized in Windows Phone 7.
Windows WhatsApp Phone 7 worth it, make an effort and show that we are many!
The WhatsApp for Windows Phone 7 petition to WhatsApp.com was written by Juanjo Sanchez Bello and is in the category Internet at GoPetition.