With the trial BES system currently installed on MAST it is possible to characterise relatively high-amplitude density turbulence at the periphery of L-mode plasmas and also to localise coherent MHD at the edge of H-mode plasmas. It is not possible, however, to characterise the core turbulence with confidence due to the limited signal level. Using these results, simulations of the BBS system have also been benchmarked against experiment. This gives confidence in the predicted performance of a BES 2D imaging system, which is planned to be built for MAST in 2008. This system is to utilise in-vessel optics with much increased étendu (x40) and should be able to detect fluctuations at the 0.3% level at 1 MHz bandwidth. It is planned to use a custom camera based on an 8x4 channel APD array sensor (Hamamatsu S8550) imaged with direct coupled optics to a l6×8 cm2 region in the plasma. With such a 2D imaging system it should be possible to observe turbulence flow patterns and features such as CAMs and zonal flows, as have been observed using the system installed on the DIII-D tokamak .