One other proposal that has surfaced for the definition of a planet is to accept anything that has an intrinsic magnitude (brightness) that is equal than or larger than Pluto's. This would keep Pluto as a planet, and would also include 2003UB313, a.k.a. Xena, which would then (I suspect) be named in accordance with the naming rules for planets (names of Greek gods). Nothing else would make the cut, though — Sedna, Ceres etc. would not be considered planets.
The IAU conference happens over the next two weeks, and a blog with information on everything that happens (not only about Pluto, of course) is at http://astronomy2006.blogspot.com/.
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