I gave it a whirl to get ready for my seminar in Austin on Wednesday and found that the description of one of the new features is a slight understatement. On the download page it says:
A few of the improvements you can look forward to in this release are an integrated debugger, integrated XSL transformation capability
Well, upon further examination, it turns out that the XSL transform capability is in fact the BizTalk 2004 Mapper. It's installed when you install the new Metadata designer -- free …
Anyway … IBF 1.5 is a huge, huge improvement over 1.0. Big kudos to the IBF team.