Sigma has introduced (July 10th) a new 1:1 ratio macro lens. The new Sigma "MACRO 70mm F2.8 EX DG" is digitally enhanced for better performance with digital SLRs that sport APS-C sensors. Being part of the "DG" series, you can expect superb performance and clear images. Here's a picture of it (from Sigma's website):

With a focal length of 70mm for film users, that translates to 105mm for digital SLRs with APS-C sensors, a great telephoto lens length. Having a 2.8 aperture, this lens should be a favorite among wildflower shooters.

At this time the lens is available in Canon and Nikon mounts. Sigma's website says launch dates for "Sony" and Pentax mounts are still listed as "TBA" (to be announced). Sigma has the best line-up of Pentax compatible lenses of any third-party maker, so, this should keep Pentax shooters visiting the Sigma website (http://www.sigmaphoto.com) for a while.