I am not a fan of IE so I would pass and just wait until the final version comes if there are no new big hits like the new pro-standards role in IE 8. It was released recently with some pretty exciting improvements and features. And I am testing it now, same as many of others, to wish this new promised to be standard-compliant version of browser would be as good as it was promised. It is sure that the biggest achievement of this version of IE is the new pro-standards role but it also has some neat features like activities and webslices that sound should bring us the some new experience when surfing the web.
So far, after doing some quick test, it seems faster than IE 7 but some of my websites don't display normally as they do in Firefox but I haven't dug that far to discover what caused it.