Chances are you've stumbled upon this blog via the developerWorks space Domino Portal Integration. If not, take a look at the updated content. Much of it pertains to how you can achieve integration between the Lotus and WebSphere Portal offerings. Some of the integration content is obvious, such as the DEPP portlets literature, while other content might just point you to a new unexploited API.
The Lotusphere 2009 presentation, Build for Success: Getting the Most Out of Lotus Collaboration and Social Software, hits on the topic of integration. To be more specific, here's the "it's too late to update" abstract:
In this technical session, we'll explore a number of ways to integrate the latest Lotus products into WebSphere Portal including Lotus Domino, Lotus Quickr, Lotus Connections and Lotus Sametime. Beginning with off the shelf products, we'll discuss and demonstrate how you can quickly deploy an integrated architecture. We'll also discuss the technology foundation found in many IBM products, and how you can discover integration points for instant re-use. The latter half of the session will be a series of design and business problems, and how IBM software and application development can be used to solve those problems. One such solution involves recreating Sametime integration to deliver substantial performance improvement in WebSphere Portal. All of which is easier than you might expect.