Leigh is now advertising a new, smaller dovetail system called the D1600. It's a 16" wide unit with adjustable fingers for both through, half-blind and sliding dovetails with a list price of $299. For those of you who read Fine Woodworking, the ad is on page 19 of the new April 2005 issue, but more details are at the above link.
It looks like an interesting alternative for folks who want a Leigh jig, but are uncomfortable with the cost for the D4. Like Akeda, they offer an accessory kit that adds some dust collection capability as well as additional cutters to the 3 that are included with the jig. The one thing I can't tell from the photos is relative to the fingers...they appear to be one-piece, rather than split like they are on the D4. But they are not done adding information to the site. It will be instructive to see this new jig demonstrated an one of the shows!