I'd be a little concerned about the new Joomla (1.5). Most of the popular components have not caught up and stated that they are ready for prime time in the new version. But the 1.x versions rock.
here is a sample site that uses wordpress and then tweaked for a more professional look http://www.blueseo.com/
I've used Joomla on a few sites (here is one RotoTown.com for a friend) and it has tons of mods for it as well as themes. I just tried to do this site in Drupal, but the links/menus just didn't make sense and after spending a few hours not getting anywhere I went back to wordpress.
Really... because I can tell a Joomla site from any other site almost the second I lay eyes on it... and I can usually find a few holes in it's architecture as well just by looking at what a search engine has on record for it... Maybe there are specific versions which have problems and others which are better... maybe it's just so widely used that some people have the ability to mess it up and fast... Joomla is worth about as much as you pay for it... jmo...