Symbian are not that popular in US mobile market, they rank on third position and have rather small market share,this is entirely different to the global mobile market share, where Symbian has over 80% monoply.

The Main reason for this is that Nokia dont have many good CDMA phones that are needed for Verizon Wireless and Sprint wireless carriers. Apart from that the GSM wireless carriers from USA which are Cingular and T-Mobile  often force Nokia to release particular phones to USA market, they control demand and supply.
This time around the year several new Symbian phones with HSDPA are about to hit markets in first quarter of 2007 (mainly from Nokia, Samsung and LG), but for now the Motorola Q which is a Windows Mobile smartphone edition (MS Smartphone) is a market leader in USA

Top smartphones in sales from August through October in united states are as follows:

1. Motorola Q

2. Palm Treo 650

3. Verizon Wireless XV6700

4. Palm Treo 700p

5. BlackBerry 8700