There were a session at the WPC 2011 (Microsoft World Wide Partner Conference 2011) called Microsoft Middleware Strategy and BizTalk Server Roadmap.
A summary of this session was post by Richard Seroter and He seems to think that BizTalk is not dead but it’s going away in a few year. Indeed, since the BizTalk Server 2004, which introduce the pub/sub engine, dev in VS orchestration designer etc… there were no new significant innovation but just some evolution according to the .Net platform.
In his post, he explain that BizTalk is “still a valid choice for a very large set of customer”. (but it’s not the only choice)
So what next ???
It’s seems the future is a little bit different because, while we try to adapt some components and software from premises to cloud, the strategy of Microsoft is to build new solution on the cloud and then adapt these solutions on premises server. (BizTalk seems to be maintain for few year).
( A preview of the next BizTalk Server Platform with AppFabric Integration ?)
For the developers, this means that people have to diversify the skills around the Microsoft platform (SQL , Stream Insight, CRM, SharePoint) and Azure.
For the organizations, a slow migration to the cloud platform (So BizTalk skill are really useful) and other technology.
The future seams to be really interesting with the use of nServiceBus, WCF Routing Service, AppFabric Service Bus and other Microsoft Technology.