These renderings have been circulating on the web for a couple of years now (thanks to Fritz at Cyclelicious for reminding me about them). This summer, a few bloggers picked up on a press release stating that these concepts would be released by Specialized in 2006 as the new Venom line. Treehugger was one blog that originally posted the press release, which was dated April 1st. Readers quickly responded that the source, Loof Lirpa Publishing, did not seem very credible (read it backwards). If you look closely, you can see that the last concept has a Bianchi logo on the fork.
Real bikes or not, these are great renderings done by the talented designer and Illustrator Scott Robertson. Check out the product design portfolio on his website for more illustrations including several additional bike designs for Specialized, Bianchi, and Kestrel. Of particular interest is the tutorial, which shows how he did one of these Photoshop renderings. Really cool stuff and, intended or not, the fact that these images are all over the web is a great example of viral marketing. If Specialized is not officially behind the circulation of these images, they should be.