At Web 2.0 Summit yesterday, John Battelle questioned Chris DeWolfe of MySpace about what he’d do if he woke up one morning and found out that Facebook had launched a service with iTunes. While Chris didn’t speculate as to what actions he would take it was clearly not a bad idea. So what is holding Facebook back?

The first issue would be the release of a music service which competes directly with existing applications such as iLike. Mark Zuckerberg historically has a relatively close relationship with the Partovi brother who run iLike. One would imagine that this has something to do with iLike being featured in the “Great Apps” program which increases invite limits to 60 per users in addition to other benefits.

Another issue would be that it would require iTunes being interested. Ultimately the combination of music products and community is a killer combination and iTunes and Facebook are both the worldwide leaders in each respective category. Yesterday, Chris DeWolfe explained how MySpace Music is heavily focused on community as it integrates directly into the MySpace network.

Imagine being able to load up your iTunes application and start playing your favorite tunes and check out what your Facebook friends are purchasing and listening to (as pictured below). This would be a killer combination and given that iTunes has become one of the primary (if not the primary) music players for consumers, this would provide both with a massive opportunity.

Such an agreement would also make it so that Facebook could avoid having to negotiate agreements directly with music industry executives. Instead Facebook gets to focus on what they do best and Apple focuses on what they do best. Facebook also gets to generate revenue through recommended music.

This sort of revenue model brings up one other inherent conflict: why use Facebook for the community component when Apple can launch their own? The only answer I have for that is so that the information is more readily available. If a user’s profile is updated with the music they’re listening to and a link to iTunes, there is a much larger marketing opportunity for Apple beyond their existing user base.

Aside from that, a Facebook partnership with Apple iTunes is little more than speculation at this point. It makes a lot of sense though.