WotC R&D took a lot of ideas from outside Eberron and used them as inspirations for Eberron but the core concept of those other two settings would still be distinct from Eberron which has a specific theme (was it Pulp/Noir aka Indiana Jones + Maltese Falcon).I seem to remember reading somewhere that WotC took the best parts of those two settings and integrated them into Eberron.
Bill Slavicsek mentioned that dinosaurs ended up in Eberron, aka Talenta halflings, because submission after submission after submission of the 11,000 featured some dinosaur theme. So Bill, head of D&D R&D at the time, took that as a market research indication that fans loved dinosaurs in their D&D. The dinosaur idea didn't specifically come from any single submission.
I don't remember an admission that they stole from the other two finalists (because they were pretending at the time that they might use the other two). I freely admit someone could produce a link that proves my memory is faulty.