Another 1.5 million subs forecasted in Q4.

The two satellite radio companies added nearly 1 million subscribers in the third quarter, on track to hit 9 million subscribers by the end of the year.

Although Sirius Satellite Radio still lags XM Satellite Radio in subscriber count by a wide margin, Sirius is signing subscribers at a faster rate than XM. On Tuesday (October 4), the company reported it had signed 359,000 new subscribers in third quarter a 97 percent increase over the same period one year ago. XM announced Monday it had added more than 425,000 new subscribers in the quarter, a 48 percent increase.

With the additions, XM has 5.03 million subscribers to Sirius' 2.17 million.

Based on Sirius' new programming for 2006, including Howard Stern and Martha Stewart, Sirius is bullish on closing the gap with XM. "The third quarter was the best third quarter in our history, and increased our market share from the year-ago quarter by more than 20 percent," said Mel Karmazin, CEO for Sirius, which expects to reach 3 million subscribers by the end of the year.

XM, which forecasts it will have 6 million subscribers by the end of the year, also proclaimed the third quarter the company's best ever. "This continues to be a phenomenal year for XM, with more than 1.8 million new net subscribers since the beginning of 2005," said Hugh Panero, president and CEO for XM. "We expect fourth quarter to be the most successful in the history of our company."

Jonathan Jacoby, an analyst with Banc of America Securities, is forecasting the satellite companies to sign up 1.5 million new net subscribers in the fourth quarter.