Geared, all the way. 2 main reasons: accuracy, and weight (which is good, unless its a tiple, then its just "okay").
I would imagine that most `ukulele players haven't been exposed to GOOD geared tuners, hence the preference for friction (those with pegheads or midrange instruments like a Kamaka Tenor (with Shallers) wouldn't fall into the most category), or they haven't been exposed to an instrument that takes advantage of the weight. And that's okay, it'll come, eventually, hopefully, maybe. Again, general statement - I know there are some that don't care about a light weight headstock, so frictions (and pegheads) are perfect for them.
Just to take it a step further, which one, & which type? For the most part, sealed for me. Gotoh geared mini, but I'd take Shallers as well. Grovers are a little loose, and oxidize fast. If Gilbert ever got into upright geared, it would be them (even if they do cost about $50 a tuner). Gilbert and Hipshot would be the open geared exceptions - someday I'll get a Hipshot set for an `ukulele, but I'll make sure the neck is stiff when I do. I LOVE the Hipshot Ultralights on my Bass, which doesn't need added weight on the headstock - the neck through design and string through body bridge takes care of all the sustain I need.