...I haven't heard this from any other sources so I just thought I might give everyone a heads up, if you use the right mouse button in 1.8 while holding a sword it blocks! So I uploaded this screenshot.

Overall the 1.8 pre-release is awesome!!!! You guys should check it out if you haven't already (even though tommorrow there will be a MUCH more updated and less buggy full-release for all minecrafters)

screenshot of sword blocking on my flickr account: http://www.flickr.com/photos/theyattway/6138217324/in/photostream/lightbox/