(For context-setting, also see Enterprise 2.0 impressions: Lotus Notes is everywhere)
One significant change I observed at the 2011 Enterprise 2.0 conference (#e2conf) in Boston, especially relative to the first few years of the conference (2005 - 2006, when it was called the Collaborative Technologies Conference), is the fact that Lotus Notes was nowhere to be seen. There were no Lotus-yellow shirts, banners, or hand-outs at the IBM exhibit hall booth, no mentions of either "Lotus" or "Notes" during the Tuesday IBM keynote session or Tuesday IBM-sponsored breakout session, and no vendors competitively positioning their offerings relative to Lotus Notes (although a few, when asked, referenced the ability to leverage content stored in Notes databases, e.g., in search results).
The IBM employees working in the IBM exhibit hall area were primarily focused on social business solutions based on IBM Connections (formerly known as IBM Lotus Connections), IBM Sametime (formerly IBM Lotus Sametime), and IBM services (both professional services and software-as-a-service offerings). When I asked, one IBMer explained that Notes is still IBM's enterprise messaging solution (i.e., its competitor to Microsoft Exchange), but it’s clear that Notes is no longer IBM's strategic solution for enterprise collaboration (it’s also clear that, generally, e-mail is considered a commodity roughly as exciting as traditional telephony).
Imho, this IBM strategy shift is both reasonable and necessary. Notes was a pioneering product for seamlessly integrated communication and collaboration, starting in 1984, and building on earlier work done by collaboration-focused project teams such as the PLATO project at the University of Illinois. It's now clear, however, that the Internet won -- modern collaboration/social systems (such as IBM Connections) began by building on the Internet architecture, the Internet information model, and Internet-centric standards, rather than by extending a proprietary and tightly-coupled product architecture that was first defined more than twenty-five years ago.
There is still a large global installed base for Lotus Notes, and there will no doubt be gainfully-employed Notes system administrators for years to come, just as there are still xBASE, COBOL, and even RPG job opportunities. Beyond its enterprise messaging capabilities, however, Lotus Notes should be considered a legacy product at this point. Its collaborative application and content platform capabilities are still useful, but they are out of step with current market dynamics, and even IBM now explicitly encourages you to look elsewhere (i.e., IBM Connections) for collaboration social business solutions. There was a point, several years ago, when it appeared possible that IBM was going to be able to sustain a "dual-lane highway" for its Notes and more Internet-architecture-focused customers, but that approach was unsuccessful for several reasons, and IBM is now strategically focused on Connections and other IBM WebSphere-based offerings.
These market dynamics should make for an interesting Lotusphere 2012. I won't be surprised if the first thing introduced at the January 2012 event is a new name, for future annual events, because the Lotus brand and Lotus Notes, for the most part, are history.