Earlier today, I had an interesting conversation on +AJ Kohn's Google+ update about how businesses are cooling on Facebook. The key observation: Facebook makes it less likely users will see your updates UNLESS they heavily engage with you. Otherwise, you have to pay, per post, to guarantee reaching your fan base. For a large brand, this can come into thousands of dollars per post.
Not hard to see why businesses might be disgusted with Facebook.
More interestingly, AJ, +David Iwanow, and others seem to feel the real ascendant social network is Twitter while +Jesse Wojdylo and I are more of the opinion that the winner lately is the hashtag (# plus a word or group of words with no spaces between, for instance #facebook). Although hashtag functionality originated on Twitter, it is now built into a number of social networks (Google+, Pinterest, etc.) and allows you to easily indicate that your update pertains to a topic that many others may also be discussing. If you click on the hashtag, you are typically taken to a list of other people's posts containing that tag, often updated in real time.
So, it makes sense that advertisers have lit on hashtags as a way to generate buzz about their brands wherever the particular person may prefer to contribute. For example, during the super bowl there were 26 online calls to action that utilized hashtag calls to action and only three that mentioned Twitter.
AJ's counter is that people think Twitter when they think hashtag. After all, the hashtag originated on Twitter. He's running a survey to test this assumption. To me, the fact that AJ is even running a survey basically cedes the argument that it's about the hashtag first and any use on Twitter second.
Brands are understandably trying to reach users first on the networks they use.