BCS is now available in SharePoint 2010 at the Foundation level.
However seems that some people inside SharePoint team and Visual Studio team did not got the memo
The code to install the BCS model is only available inside a dll that is installed with the Standard/Enterprise edition of SharePoint 2010 Server.
I have just published a new project on CodePlex: http://bcsmodelreceiver.codeplex.com/ that will install the missing code as a Farm feature and will permit to install your BCS Model feature correctly on any platform. It is a Farm feature that will ease the pain of deploying BCS Models inside SharePoint 2010 especially the Foundation.
The code used in this project was actually published by Microsoft at: http://code.msdn.microsoft.com/BDCSPFoundation The only thing I have done is to put it together as a reusable feature so you do not have to cut and paste the code in each of the project.
Now, to use this feature, there is a small tweak that the developer has to do in Visual Studio, and that is to reference the BCS Model Feature Class from this project.