ESB vs Biztalk

Today I was in a seminar organized by Microsoft on interoperability. I was listening to Lorenzo Madrid and found it interesting to know his view point on open standards and interoperability. He is of the opinion, interoperability can be achieved even without open standards. Based on my questions he may have realized that I share a different opinion on the topic.

However, later on one of the example projects they have done using Biztalk lead me to read bit more about Biztalk and I found this interesting post. Of course this is an old post;

http://oreilly.com/pub/wlg/8484

But has Microsoft change their view point later on?

http://blogs.msdn.com/mohammadakif/archive/2007/01/23/microsoft-s-enterprise-services-bus-esb-strategy-part-4-4.aspx
http://www.infosysblogs.com/microsoft/2006/09/biztalk_as_an_esb_2.html

Now what they have is a set of guidelines as to how to use Biztalk as an ESB.
http://www.microsoft.com/biztalk/en/us/esb-guidance.aspx

Hence, the fundamental issue still remains. Of course when you look at most of the J2EE based ESB implementations, I don't see a different with them and Biztalk.

One example of a real ESB, in my opinion, is here....
http://synapse.apache.org/