"XM and Sirius just cleared the largest (and longest) hurdle on their path to getting all conjoined: The Justice Department officially okayed Sirius's $5 billion buyout of XM. They said that the growth of mobile broadband "made it even more unlikely that the transaction would harm consumers in the longer term," squashing arguments from radio and broadcasting groups the merger would be anti-competitive. Onward to the FCC and fickle, fickle Kevin Martin, though the odds of this happening just got much, much better."
http://gizmodo.com/371542/xmsirius-merger-approved


So my question is, will XM playback on the G8 still work after this merger? Will the newly combined service play on both XM and Sirius receivers?

From the press release of the DOJ's findings, it appears that the answer to your question is no... You would still be able to use XM but not be able to use Sirius with it


As to existing subscribers, the Division found that satellite radio equipment sold by each company is customized to each network and will not function with the other service. XM and Sirius made some efforts to develop an interoperable radio capable of receiving both sets of satellite signals. Depending on how such a radio would be configured, it could enable consumers to switch between providers without incurring the costs of new equipment. The Division's investigation revealed, however, that no such interoperable radio is on the market and that such a radio likely would not be introduced in the near term. For example, in the important automotive channel, such a radio could not be introduced in the near term due to the engineering required to integrate radios into new vehicles. The need for equipment customized to each network means that in order to switch from XM to Sirius, or vice versa, a subscriber would have to purchase new equipment designed for the other service. In the case of a factory-installed car radio, switching satellite radio providers would have the additional disadvantage of requiring an aftermarket radio that would be less integrated into the vehicle's systems. Data analyzed by the Division confirmed that subscribers rarely switch between XM and Sirius.

Link to story (https://us.etrade.com/e/t/invest/Story?ID=STORYID%3Detrade_2008_03_24_eng-etrade_cbs2_market_watch_eng-etrade_cbs2_market_watch_C3DCF567-B272-4C36-9930-75E45F25FC28&provider=PRNewswire)

So my question is, will XM playback on the G8 still work after this merger? Will the newly combined service play on both XM and Sirius receivers?

Just a quick addition, a combined Sirius/XM company would be committing suicide by making older receivers obsolete. They would be making the millions of OEM receivers obsolete and of course the retail receivers obsolete.

This would alienate and piss off the entire customer base.

Of course, all existing radios will be able to receive their current programming.

However, new equipment may need to be bought in order to have both XM/Sirius channels available on one unit. But I think they will put forth a lot of work to try and avoid that.

The truth is, they want everyone that owns a Sirius or XM receiver to be a customer. Making the old radios obsolete would just piss people off and would probably cost them untold amounts of customers.

Disclosure: I am a Sirius shareholder.