thanks joey! just started actually playing the uke myself even though i signed up here 3 years ago and first time i saw your posts; really a great idea! i wasn't aware until reading a bit of this thread that these were from the Daily Ukulele book...i've seen it on amazon but haven't gotten it partly because i already have about 4 fakebooks that i mostly use for piano so am hoping i can muster some tunes out of those.
Perhaps my inexperience so far in playing the uke but was having a hard time making those chords work for that tune; actually was having better luck with the C Em F G i had come up with. As far as the baritone you can play it the same way only if you try that the tune will be...well if you were playing an a chord on the soprano uke and played the same chord on the baritone it would sound like an e chord (think i have that right!) where the uke is tuned higher than a guitar, as if you had a capo on the 5th fret of a guitar. but as far as the overall sound it would be the same, only lower on the baritone.
anyhoo, that's what made me think it might be an open tuning because i couldn't quite replicate what he was playing...especially the last, 4th chord, where he seems to be lifting all his fingers and just playing all the open strings. oh well i'll have something to work on trying to figure it out! Really love the casual rambling way he plays this though...every once in awhile you come across a youtube video that is just great like that, not necessarily flash virtuoso but just unique and right in that zone...reminds me of a guy on youtube who played 'my favorite things' on piano and just hit it right on like that too.