How does one learn SharePoint? SharePoint development roadmap?

This is a broad and general question I know.  What are the suggestions for learning SharePoint development?

Start with SharePoint Designer?

Does one need to first learn .Net coding first?  Using MS Studio uses this.

I've done SharePoint site administration for a couple of years, building sub-sites, lists, etc in a SharePoint 2007 environment, but now i'm wanting to get deeper into the development using Designer and/or Studio, depending on the request.  I will start down a path of learning Designer, then I'll find myself looking at code and wishing I would stop and learn more .Net development.

I"m looking for a suggested roadmap for one to use in getting into SharePoint development.

Thanks

Michael Montgomery