Maybe I'm dating myself, but I remember when SharePoint didn't exist. That's right folks. There was a time when SharePoint was only a gleam in an engineers eye and I certainly hadn't seen it! Back in those days people talked about information architecture, document management and yes, enterprise content management.
Now do not mistake me for one of those people who extolls the virtues of the past. Quite to the contrary, I remember many a long night with a text based SQL server interface where I longed for a simpler way to provide solutions to my customers. I just didn't think it needed to be that hard to structure metadata or provide a custom interface for people that they'd actually want to use.
The one thing I will note is that in those days we did thoroughly understand the need for strategy and structure prior to doing that enterprise software install! Enterprise content management strategy was the backbone of the implementation of these sorts of custom systems. Now, however, since everyone can hit File:Run:Install things have changed.
This is why I feel its important to understand and master ECM strategy before delving into the depths of SharePoint or any other ECM system. It may not be sexy, but it will still serve as not only the backbone but the roadmap for your implementation. AIIM offers both types of training courses (ECM & SharePoint) and there is a lot of other written material available.
Understanding the depth of services you want to offer, the requirements for them and what SharePoint can offer in these various areas will make you a better SharePoint professional. You don't have to take on writing an entire ECM strategy to have the segments inform your opinions about implementation and development.
I still feel today that its our responsibility as technologists to aid our business leaders in making smart decisions. Educating yourself about the overall goals of ECM prior to the specifics of a platform like SharePoint will help you do that.