Many thanks to Jnobianchi and Ray for a little more perspective of the range of ukulele players in the "traditional - not hawaiian?" styles.
I couldn't find everyone Jno mentioned, but those I did, I enjoyed. Ray, I have heard a bit of Lil' Rev, but that website gives a lot of complete songs to hear - gives me a much better appreciation of what he does.
That being said, I still have to admit I am rather amazed at Jon's talent as both an overall musician and as an ukulele player. He seems to let the overall musician part take precedence, as it should - there's no doubt a significant part of the package are the vocals.
In the one CD I have (Canoodlin'), it is also evident that he is very good on mandolin, banjo, and more. The arrangements are first rate as well. The best comparison I can make to what he does is to the "King of Mainland Ukulele": Wendell Hall. He was also adept at a number of instruments, and also a student of "historical forms". He pretty much singlehandedly brought back the music of Stephen Foster. If Jon had been born a hundred years ago, (and had an aptitude for self-promotion) I think it's possible we could all be collecting old "Eugene" model ukuleles today.
Do you think maybe this guy is a lttle underrated? He's a very familiar presence here, after all, and extremely prolific with his videos. As OldePhart mentioned, his CDs are not "overproduced", but I like that aspect very much as well.
For those who haven't heard one, I'd really recommend one of the CDs. In addition to the all the traditional music, he'll throw in a "Space Girl's Song" and such, and make them sound traditional as well. Keeps it all very entertaining.
His music has that good/bad aspect that comes from fine musicianship. I find one after another of these songs will stick in my head all day long. Never know which one will take over the brain on any given day, but they always make the day go better.