Chicago (IL) – T-Mobile’s upcoming G1 may not be the best-looking iPhone rival, it may not have the most complete feature set and T-Mobile may have undersold the device at the recent launch event. But it seems that the device is already selling like hotcakes – 1.5 million phones have been snapped up by t-Mobile customers so far.  

T-Mobile and manufacturer HTC apparently believed they could sell about 700,000 G1s by the end of the year – an estimate we found to be very optimistic. But it seems that a 700,000 estimate was much too conservative: T-Mobile reportedly sold out of its 500,000-unit batch within a few days and decided to triple its order to 1.5 million units. Those additional 1 million phones are also gone, according to Fool.com.

With all G1s being sold for now, it is unclear when retail sales for the G1 will start and how many of those Android-based phones will be available for the Christmas season. It is quite apparent that there is a huge demand for a new generation of smartphones, which may also be a good sign for RIM’s Blackberry Storm and Nokia’s 5800.

It is interesting to note that each of the three iPhone rivals has one particular strength, but it is unclear whether any of those new phones can offer a compelling combination of those features in a similar way as the iPhone does. The Nokia 5800 is likely to emerge as a great entertainment device and the RIM Blackberry Storm as the best business device. The G1 focuses on an open, easily expandable platform.     
 
For Google, the gigantic number of pre-orders - which exceed Apple iPhone 3G first-day sales – means that Android will have to deliver. Missing features such as the Bluetooth API should be delivered ASAP and the Android Marketplace needs to get up and running in a timely fashion. Oh, and HTC may want to think about adding a headphone jack to those G1 phones.   

The G1 will begin shipping on October 22 for $179 (2-year contract required).