Is a rogue 'exoplanet' classed as a exoplanet? Given that the term planet strictly (according to the IAU) refers to a body around the sun, rogue planets can't be called that, so I assume they must be called rogue exoplanets?
But do they even qualify for the name exoplanet? Given that they do not orbit a star?
 A: They are not rogue exoplanets according to the IAU, but "sub-brown dwarfs;" only objects actually orbiting stars or stellar remnants are "planets." This is a temporary working definition instituted in 2003; it isn't set in stone. See here the IAU working group's full explanation.
A: Remember the searches for "conventional" dark matter?
After all the WIMPs, someone had to come up with MACHOs.  Extensive searches were made for dark objects roaming the interstellar space, by watching for microlensing events within our Galaxy (or involving stars in the satellite galaxies such as the Magellanic Clouds).
In the papers describing these efforts, one class of proposed objects were "rogue planets" (not rogue exoplanets) and, apparently, no one had any problem with the phrase.
Of course, that is a moot point, since they did not find anything smaller than brown dwarfs.
However, some of these objects have been recently discovered (10-Jupiter-Mass objects) and the article I just read uses the phrase "unbound planets"
"Bound and unbound planets abound" by Joachim Wambsganss. Nature, v.473, pp.289-291 (19 May 2011)
A: Strigari et al in http://adsabs.harvard.edu/abs/2012MNRAS.423.1856S refer to unbound planets as "nomads" and notes that "in the literature a subset of these are sometimes called free-floating or rogue planets" (Abstract).
