ESB is heavily focused on message-oriented processing, but adds the complexity of events to the mix. Unlike legacy EAI solutions, ESBs generally transport messages on the bus in a neutral XML format and then convert messages to the format (JMS, EDI, MQ) used by the endpoints receiving the message. Events are nothing new, but they become more business-oriented when combined with business processes and will require even more input from line of business counterparts than in the past.
ESB is considered the underpinning of a well-designed SOA, so if you haven't yet implemented it, then you're likely to in 2006. Gartner says that ESBs will "supersede several types of traditional middleware during 2005 through 2007 because ESBs are better-suited to modern application styles, such as service-oriented architecture (SOA) and event-driven architecture (EDA)."
To support an enterprise SOA, your ESB must support myriad data sources and points of entry, so make sure you coordinate across business units to determine what features it should support. Carefully consider the architectures of different ESB products such as those from Cape Clear Software, Fiorano Software, IBM, Iona Technologies, Oracle, PolarLake and Sonic Software, to determine which is best for your performance and deployment needs.
Bye-Bye, EII
You'll either replace your database or at least massively upgrade it. 2006 promises to be a year full of interesting database activity as IBM, Microsoft, Oracle and Sybase all release new versions of their respective database platforms.