The identities of Microsoft's two online brands, MSN and Windows Live, have been a subject of confusion since the company launched the latter a few years ago. So it was interesting -- and a bit perplexing -- to see these billboards show up in Seattle recently.

Here's why: Microsoft has positioned MSN as a destination for "programmed content," such as the MSN.com portal, MSN Video and MSN Games. Windows Live, on the other hand, has been designated as a place for communications (Hotmail, Messenger), user-generated content (Spaces), and information retrieval/question answering (Live Search).

At first glance, the messages on these billboards seem more about retrieving information or answering questions: "Sherlock had Watson. You have us," reads one, south of downtown Seattle. Of course, that puts the consumer in the role of the famous fictional detective, digging for clues ... and MSN in the role of the not-nearly-as-sharp sidekick.

"Free IQ points. Collect them all," reads another, along Elliott Avenue West. Again, that might conjure up images of a hunt for information.

Granted, it's not easy to be nuanced in billboards. In fact, in response to my inquiry about the billboards, an MSN representative explained that they're part of a larger campaign that includes an online site, www.noonewantstolookdumb.com, radio spots, and related online videos. The underlying idea is to promote MSN.com's informational features and news as a source of knowledge. For example, one video shows a guy panicking about all the subjects his date might want to talk about. And the radio ads include one that promotes MSN's ability to "expand your mind."

Microsoft says the radio ads and billboards are running in Seattle, Chicago, Los Angeles, San Francisco and New York.

Here's how the company explained the branding issue in response to my question about it: "MSN is being promoted because it provides an important layer of programmed, editorially selected content that helps ensure our readers stay in the know. Windows Live is a complementary brand to MSN that helps users stay connected with each other."

But considering how much confusion there has been between the two brands, it's curious to see MSN ads using slogans that might apply just as easily to the company's Live Search engine. At the very least, it seems to illustrate the challenge the company faces as it tries to distinguish between the two. It will be interesting to hear what everyone else thinks.