I think that it can look great if text flows around irregular shapes. Something which have been possibel for years on DTP (Desktop Publishing). We are getting the same effect here on the internet soon when CSS3 regions will be ready for release.
I have found and testet a jQuery plugin which in a simple way adds such “knocking out” features to your webpages.
To the left you can see a test/demo page in which I have written about how you can use it and how I found the plugin.
Read and see the plugin in action here: “Testing SlickWrap jQuery plugin”