WISE

A 0.5–20 Jupiter mass object with a temperature 250–400 K. May be either a brown dwarf or a free-floating planet.

The Coldest Brown Dwarf (Or Free Floating Planet)?: The Y Dwarf WISE 1828+2650
http://arxiv.org/abs/1301.1669

The Closest Star System Found in a Century
http://science.psu.edu/news-and-events/2013-news/Luhman3-2013

WISE J104915.57-531906.1, a brown dwarf binary at 2.0±0.15 parsecs. Primary is L8±1, secondary near the L/T transition.

The best estimate of the distance (ignoring the error bars) puts the binary slightly further away than Barnard's Star.

WOw!
Edit: Now on arXiv.
http://arxiv.org/abs/1303.2401

More on WISE J104915.57-531906.1
http://arxiv.org/abs/1303.5345

Offers also some more memorable designations for the system: "Luhman 16" (its preliminary WDS designation) or maybe "Luhman-WISE 1".

Why not Luhman's Star, like other nearby stars named after the people who discovered or recognized them?

It'd be a bit weird calling it "Luhman's Star" when it is two stars, no?

Heh, that's true...

A binary star is still "a" star

Seem to be quite a lot of papers coming out on the arXiv about this one...

Radial velocities confirm the system is bound, spectral types given as L8±1 and T1±2. Also gives estimated masses for assumed ages of 1 Gyr and 10 Gyr.

Characterization of the Nearby L/T Binary Brown Dwarf WISE J104915.57-531906.1 at 2 Parsecs from the Sun
http://arxiv.org/abs/1303.7171

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The system is a flux-reversal binary: the secondary is brighter than the primary at 0.95 – 1.3 microns. Spectral types given as L7.5 and T0.5.

Resolved Near-Infrared Spectroscopy of WISE J104915.57-531906.1AB: A Flux-Reversal Binary at the L dwarf/T dwarf Transition
http://arxiv.org/abs/1303.7283

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Variability on Luhman 16B (they use the Luhman 16 designation throughout most of the paper instead of the WISE one), probably weather-related.

Fast-evolving weather for the coolest of our two new substellar neighbours
http://arxiv.org/abs/1304.0481