I suppose we need to understand what makes someone 'skilled' as opposed to just very good at it? Official training? Lots of experience? Views of peers?
At work I pride myself in my technical skills. I am considered the techie at Barclays/Accenture BDCN in anything to do with WebSphere Application Server, Java (especially from a performance monitoring/tuning perspective). I guess I am also a bit of an expert in Linux in that I understand the vast majority of it such that I can alter source code for my own purposes and fix broken implementations. Yet I have no 'official' exam or certification in any of the above. Does this make me skilled or just very good at it?
Not that it bothers me either way. I enjoy my job, I enjoy learning new skills(off to London in 6 hours for a course in WBIMB(Go on Google it, I dare you

)) so I'm happy with my lot.
Ian