At Lick Observatory, we surveyed 107 G and K stars. Of these, 7 stars have "planetary" companions, with M sini < 10 Mjup. However none of our 107 stars exhibits a companion that has Msini = 10 - 80 Mjup.
Brown dwarfs are rare around Solar-Type stars. At most 1% of Solar-type stars has a brown dwarf within 5 AU. Thus, planets are distinguished from brown dwarfs by virtue of their relative occurrence.
Apparently, the number of companions begins to rise at 8 Jupiter masses, and continues to rise toward the lowest detectable masses, ~0.3 Jupiters, where detectabiliy becomes poor.
At most 1% of stars harbor brown-dwarf companions within several AU. Their masses are spread out from 10 - 70 Mjup, as demonstrated beautifully by the data of Michel Mayor, Antoine Duquennoy, and Didier Queloz at Geneva Observatory and Observatoire de Haute Provence.
Eccentric orbits may occur relatively commonly for extrasolar planets. Just one eccentric giant planet orbiting a star can spell dynamical doom for terrestrial planets, and may bode ill for slowly evolving creatures. The claim that all planetary orbits must be like ours may well be a circular argument.