Sedna is located in the Kuiper Belt, a region containing hundereds of objects which are potential planets. however, the Oort Cloud seems a little too far out to house any planets in my opinion...
some of the planets discovered are really wierd..theres this one, i forget the name, but its two thirds the size of our sun, its orbital period is about 53 hours, and on the surface it snows solid iron...wierd eh? 😖
Thought I'd post another article, interesting still: http://story.news.yahoo.com/news?tmpl=story&cid=96&e=20&u=/space/weirdobjectbeyondplutogetsstranger