I'm sure I don't know what I'm talking about, but there's a lot of confusion (at least for me) around this.
Best I can tell, the Riverboat Jubilee (which actually takes place on a riverboat - i.e., the Mark Twain) is only at
Disneyland. Al Lutz who is cited in the LA Times article only talks about Disneyland and when I reported on it several days ago, it was based on Disneyland actively casting for this specific show.
Disneyland also states it will start November 6 with rehearsals beginning in October.
So I'm not sure where the LA Times got that it was happening on the Liberty Belle either. When I asked about it, Attractions Magazine said they got 'confirmation' from a 'Disney rep' for it but in their article, they seemed to have backpeddled from that and simply state it will be a special meet & greet area (under the same name)
which itself isn't a surprise. WDW is actively casting for Tiana, Naveen and Dr. Facilier for 'shows, parades and meet & greets.'
Not sure where the October 26 date came from, but I always anticipated they'd be starting in October anyway so that's probably right.
I can easily see the riverboat thing happening in Disneyland, especially with the view of the Rivers of America by NOS (if you've seen the F! pre-show there, I think it makes *perfect* sense) but I don't see that happening as smoothly in MK, let alone Frontierland.
as an aside, DisneylandNews on Twitter openly announced it yesterday. No such word from WDW.
ETA: it's also probably worth noting that Disneyland is also casting for vocalists for the riverboat show. No such comparable casting at WDW as of yet.