From Digital Photography Review:
"Sigma has today officially announced the 18 - 200 mm F3.5 - F6.3 DC OS lens. This compact lens offers a big 11x zoom range in combination with Sigma's own Optical Stabilizer. It features aspherical and low dispersion elements as well as multi-layer coating to reduce flare and ghosting. On the downside it is slow (F6.3) at telephoto (you can't have everything at this price). On a digital SLR with a 1.5x FOV multiplier this lens provides an equivalent field of view of 27-300 mm on a 35 mm camera."