We visited the VWL in December 2006 and had a "new" sleeper sofa in our 1-BR unit. The sofa was of a somewhat unconventional design (not the usual remove the seat cushions and pull up/out the folded mattress) and was quite nice. It had a firmer, less saggy frame with a viscoelastic foam (tempurpedic style) mattress overlay.
Bottom Line: it was quite comfortable and MUCH better than some of the old, conventional sleeper sofas we've had.
Incidentally, we switched units during our stay and the first unit had the old-style sofa, while the second had the new style. Apparently (at least as of early December), not all units have the newer sofas. Not sure if all old units are being replaced with the new design or if only damaged/unrepairable units are being replaced.