This InfoWorld article looks at the Dynamics dev group in Europe. They quote Klaus Holse Andersen, the newly appointed corporate vice president for Microsoft Business Solutions Worldwide Sales and Operations as indicating that unifying the 4 ERP products could take until 2012 or 2015. Along the way it seems that we will get more common ground via things like business portal and SQL Reporting Services.
MS has been headed down this road of shared pieces for a while (SL didn't have Smartlists but then it was available to them via Business Portal for example). It sounds like they are wanting more "separate" pieces that could hook into any of the ERP cores like some of the auditing software does or like Office 2007 will.
And hey, while I'm speculating, some days I think MS just likes to change its mind.
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