Diamond Source of Virginia carries it...
http://www.diamondsourceva.com/Education/Shape/diamonds-shape-springcut.asp
I recently inquired and they sent me a few examples of what they''ve got. Haven''t made a purchase yet, and not ready to, but it is a gorgeous cut! It''s somewhere between an emerald with more sparkle and a radiant with broader flashes.
Official site: http://www.springcut.com/content/index.html
The Spring Cut looks alot like a Crisscut but with less facets. Both are essentially a scissor cut mixed with a step cut. If you are looking for super sparkle then probably a Crisscut is better. If you are looking for more of a midway between a traditional emerald cut and more flashy bling then the Spring Cut is probably better.