Things never get dull for the country's lone satellite-radio provider. Shares of Sirius XM Radio (NASDAQ:SIRI) moved lower this past week, sliding 1.8% to close at $3.88. The media darling's slide was worse than the Nasdaq's 0.4% gain on the week, while the Dow 30 moved higher.

Sirius XM announced another share buyback, and the stock hit a new six-year high. There was more going on beyond the share-price gyrations, though. Sirius XM also announced its earnings call information, while Apple (NASDAQ:AAPL) is reportedly expanding its iTunes Radio platform to several key markets next year.   

Let's take a closer look.

2 billion more reasons to believe in Sirius XM
When Sirius XM announced a $2 billion buyback in December of last year, it was easy to dismiss it as lip service. Boards authorize huge repurchases often, only to find the companies lagging when it comes to eating their own cooking. Well, Sirius XM revealed that it has already worked its way through $1.6 billion of that initial authorization, and now it's going to go for another $2 billion.   

Sirius XM is also letting Liberty Media (NASDAQ:LMCA) get in on the fun. The company will buy back $500 million of Liberty Media's stock at a predetermined discount in the coming months. This will be part of the $4 billion the board has authorized for buybacks since December. 

As long as Sirius XM doesn't stretch itself too thin in reducing its shares-outstanding count, it's hard to spin this as anything else than a positive development.

Keep on moving
Sirius XM briefly hit $4 on Tuesday, establishing a new six-year high. You have to go all the way back to February 2007 to find the last time the company was trading north of $4. The interesting thing about the milestone is that Sirius XM hit this fresh high before the buyback announcement. 

Speaking of announcements, Sirius XM will be reporting its third-quarter results on Oct. 24. As usual, the report and earnings call will happen in the morning before the market opens.

If there's any disappointment in the announcement, it's that the company didn't pre-announce its subscriber count the way that it has from time to time when the news is good. Maybe it thought the buyback would be more than enough to keep the positive momentum going. In any event, it's hard to fathom seeing a bad quarter out of Sirius XM, given the strong automotive market and somewhat favorable economic trends.

Apple wants the world
Apple's iTunes Radio is only a few weeks old, but Bloomberg reports that the consumer-tech giant is already planning on expanding its ad-based streaming service to the U.K., Canada, Australia, New Zealand, and Nordic countries by early next year.

Naturally, this kind of news emboldened the Pandora (NYSE:P) naysayers. Apple is expanding abroad! Where is Pandora?

However, this is an opportunity for both Pandora and Sirius XM. One of the benefits of offering streaming -- and improving its Web-based platform, the way Sirius XM has over the past year -- is that it can now go where it couldn't as a satellite-tethered player. Obviously, global expansion is easier said than done. Each country has unique licenses and regulatory hoops to jump through. Apple has an easier path in these markets because it already offers iTunes in those territories. But it does pave the way for Pandora as an ad-based alternative, and for Sirius XM as either a standalone premium offering or by dusting off a more competitive ad-based model to take on Apple, Spotify, and others overseas. 

Longtime Fool contributor Rick Munarriz has no position in any stocks mentioned. The Motley Fool recommends Apple and Pandora Media and owns shares of Apple. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.