I write a lot about the importance of marketing and promoting "in the river" - my terminology for engaging users in the most specific and relevant experiences / locations. This concept is increasingly important new platforms (software and hardware) emerge and as those experiences consequently change. Just the other day I wrote about how Evernote has done a masterful job creating numerous applications for each native environment: iPhone, iPad, desktop, Outlook, browser, etc. This will become the norm... and the result is that targeted messaging becomes tougher and more challenging.
Here is a great example from Huffington Post (along with Google & Chrome) - who is always far along the marketing & experimental curve. If you visit their site in the Google Chrome browser, the header is taken over to promote their new Chrome Application: Newsglide. Simple - but brilliant. This messaging would be overlooked if it were a traditional location. And it would wasted real estate if it were a universal promotion. Furthermore, the promotion is native to the experience (a similar action in Firefox would look different).
It wasn't long ago that I commented on Huffington Post's in-experience promotion of their Google Chrome Application (see example here).