Perhaps you hadn't heard: Howard Stern debuted Monday on Sirius Satellite Radio.

The colorful shock jock spent much of his first day on fee-based radio taking credit for Sirius adding 2.6 million subscribers in the past 15 months and by disparaging his competitors on "boring, old-fashioned, overcommercialized radio" such as that offered by Clear Channel Radio, CBS Radio, et al.

He also introduced his new show's announcer, "Star Trek" actor George Takei, and promised that the two channels he programs for Sirius will become major providers of content for various media, adding that a webcast of his Sirius radio show already is under discussion.

In the first of what is planned as a five-hour show that will stream five days a week, Stern and his cast of players took a few music breaks to collect their thoughts and rejuvenate, but there were no commercials. Beginning today, the Stern show will feature about six minutes of ads each hour.

Sirius, which often boasts of ad-free music channels, intends on collecting nearly $60 million in ad revenue this year on Stern's two channels and the other 60 or so channels that carry ads.

Advertisers are paying about $6,500 per prerecorded ad on Stern's show and as much as $15,000 for a live read. Some of the first few advertisers lined up are Heineken, Vermont Teddy Bear and at least one online gambling company.

Of his contemporaries at traditional radio, Stern said that Rush Limbaugh has flourished only because his show begins later in the day so he doesn't have to compete with drive-time talent, and he said that he finds it "amazing" that Don Imus is succeeding given his relatively small audience. Imus' strength, Stern said, was in being "bland enough not to get fined."

He added that David Lee Roth, who took Stern's slot in some markets, has been way too secretive to connect with his audience, shying away from talking about whom he's dating, for example, and even of discussions pertaining to Van Halen, the rock band he used to front.

Sirius first announced to the world that it had signed Stern in October 2004, when the company had about 662,000 subscribers. At the end of 2005, it has 3.3 million subs.

Because the Wall Street consensus -- before the Stern announcement 15 months ago -- was that Sirius would have about 2.2 million subs by the end of 2005, the company has no problem crediting Stern's arrival with the 1.1 million sub difference, Sirius spokesman Jim Collins said.

Collins added that, pre-Stern, Wall Street estimated only 3.5 million subs for Sirius by year's end, though Sirius recently said it expects about 6 million by then, so Stern gets the credit for the projected 2.5 million difference there, too.

"We can't be certain where we'd be without Howard, but clearly a lot of that is attributable to him," Collins said.

Sirius CEO Mel Karmazin echoed the sentiment Monday at an investors conference, telling analysts that "it has been phenomenal what (Stern) has done for the company."

It has come at a high cost, though. Sirius is paying Stern $80 million per year, though production and other costs -- including the construction of an additional 4,100-square-foot studio at Sirius headquarters in New York -- comes out of that. Sirius also promised $100 million in stock to Stern if the company met certain sub-growth goals. It did, and he was recently awarded the shares, though they're worth closer to $220 million nowadays.

Always mindful of Sirius' only competitor, Collins noted that XM Satellite Radio is paying about $65 million annually for Major League Baseball, suggesting that Stern at $80 million annually was the better bargain.

Not so fast, said XM spokesman Nathaniel Brown, who pointed out that while Sirius used 15 months of Stern-fueled hype to sign up 2.6 million new subs, XM has -- quite a bit more quietly -- signed an additional 3.5 million subs in the same time frame. "That's bigger than their whole base," Brown said.

XM, which launched its service first and has never trailed Sirius in terms of subscriber base, said it will have 9 million subs by year's end.

Karmazin also weighed in on whether Stern was worth the more than $500 million it will cost Sirius during the next five years in stock and cash, telling analysts Monday that Wall Street expects Sirius to earn about $586 million in revenue this year, about $200 million more than was expected before Stern.

But the Stern effect, one way or the other, had little impact on Sirius shares Monday. They closed 3 cents higher to $6.57.

Shares of XM, on the other hand, jumped $1.99 to $29.94 on the strength of positive analyst comments Monday, especially from Deutsche Bank analyst James Dix, who upgraded the stock to a "buy" recommendation and raised his price target to $33.

Considering all the talk of Stern being unconstrained by a watchful FCC now that he is no longer on free, over-the-air radio, his debut Monday on Sirius was rather tame. In fact, he said he is trying not to curse during his show, "whatever that means. I've already broken it six times."

Stern and his troupe spent an inordinate amount of time discussing the sexual habits of Takei, who had previously announced he is gay. Stern also said he had married his model girlfriend, Beth Ostrosky, though later said he was only joking.

Stern and company even waxed on about what he had heard were disappointing boxoffice numbers from "King Kong," and Stern dismissed the movie as racist, with the ape representing "the big black man" who falls in love with a blonde. So they "drag his ass to New York and kill him."