I don't even think I can answer the question. I don't know everyone who chases, and therefore I have no idea who all has been exposed to the various impressive weather phenomena that has graced the past decade.
As others have noted, there are those who might have went inactive in recent years that had a great start to the decade, and then there are those who do not put themselves into the limelight, yet have impressive footage to pepper a very stellar "resume." In the last several years, technology has fostered live streams, more live footage from chasers on major national networks and the advent on software programs like Spotter Network. In addition, more and more chasers have started websites and blogs. All of this has catapulted the notoriety of an increasing number of chasers, though mostly since 2006.
However, most of us have no way to include very active, successful (that's an arbitrary term to begin with) chasers that just aren't as well connected because they choose not to expose themselves using one or more of the aforementioned means. However, rest assured there are chasers out there who are pretty 'successful' and have a rather stellar collection of documentation to prove it, yet they remain low-profile.