Vintage BanjoUkes?

Hey Paul- it really depends on which ones you are looking at. May Bells weigh a bit, especially the model 24 (8' head) which has a Walnut neck- the Model 20 (7" head-maple mostly) is a lot lighter. If they have a resonator, count on more weight. I have seen Le Dominoes that have really thin pots, a couple others as well, and I am assuming they are lighter. For the most part, they are going to have some heft to them- you get used to it pretty quickly.
Vintage BU's have, again typically, a thinner neck, like that of a Mandolin, which can really take some getting used to. They tend to have really nice plating on the metal bits, which is hard to do nowadays (it has been deemed bad for everything, and rightfully so) and as you said, they have skin heads- give me a day and I can throw a comparison up on the difference between skin and synthetic if you would like. The build quality of that time is so much different than it is today...shoot, if you are ever in Northern California stop by and I will show ya.
Vintage has history, but can be a pain. My first May bell needed three weeks of work to be playable- and I got to learn how to dress and level frets, set neck angle, tension a head properly etc. My second simply needed to be set to my preffered action height (John likes them a lot lower than I do) and was a whizz to get done, the third, it is still in the mail so we will see, but it is always a crap shoot. You get one from Mike at Mainland and it is good out the door.
For me the deal with the vintage is holding and playing something daily which is 90 years old...I get a bang out of that, but those Gold Tones are gorgeous, as are the Eddie Finns (played one at a festival and it was great..but really heavy).
Most the old ones are somewhere in the region of 14" in terms of scale length, but that varies, a lot, just like everything else in these old things. If you are thinking vintage, definitely go here and here and if you find one, be sure and ask. That is how I got going- be sure to ask Jnobianchi, because he is the guru. My latest (also in the mail) is an "Irish" tenor banjo, which I am going to convert into the worlds only 90 year old Baritone Banjo Uke (if Dirk will make me the strings for it ).

Thanks for all the great info

I have nothing substantive to add to Dave's great rundown, but will say that when vintage ukes were being made in the 20's and 30's, they really never told you in the catalogs whether what you were getting was a soprano or a concert. They just made them as banjo ukes - with anywhere from 14 to 17 frets (and scales varied from model to model, as Dave says), and something called a 'longscale' banjo uke. This is essentially the same model, but with a 19 or 20+ fret neck. Ludwig, Lange, Lyon & Healy, Houdlett's Nu-way/Nu-art, and a few others made longscale versions, but even these companies didn't make them commonly. I've played new and old, prefer old, but I do like what Mainland, Flea, Beansprout are doing because they're taking unique approaches, and I've even enjoyed the Lanikai, Gold Tone and Morgan Monroe varieties to a degree (though not as much, because I like the original versions of their classic approach a bit better).

If you're looking for lighter vintage instruments, I'd recommend the GS Houghton & Sons ukes (Melody, Handel), J.R. Stewart, Stromberg Voisinet, Keech and Jedson (Dalls & Sons), Gretsch, some Stellas/Schmidts, Houdlett and John Grey. These have slightly thinner pots and tend to be lighter than the Langes, Ludwigs, Gibsons, Slingerlands and Epiphones that you'll find out there. Also - 7" models are generally lighter with thinner pots than the 8" pot models.