We present preliminary astrometric results for the closest known brown dwarf binary to the Sun: V Indi Ba, Bb at a distance of 3.626 pc. With ongoing monitoring of the relative separation of the two brown dwarfs (spectral types T1 and T6) with VLT NACO near-IR adaptive optics system since June 2004, we obtain a model-independent dynamical total mass for the system of 121 MJup, some 60% larger than the one obtained by McCaughrean et al., implying that the system may be as old as 5 Gyr. We have also been monitoring the absolute astrometric motions of the system using the VLTFORS2 optical imager since August 2005 to determine the individual masses. We predict a periastron passage in early 2010, by which time the system mass will be constrained to <1 MJup and we will be able to determine the individual masses accurately in a dynamical, model-independent manner.