The revised edition of Song of Blades and Heroes (version 5.0) was announced earlier this month but I only picked up the update a few days ago. Page count has jumped from 35 to 66 but that's due to a lot more content included, not increased complexity (yay!) There are some welcome additions like the rules for free noncombat movement (to avoid having some unlucky troops stuck far away from combat) and the optional rule to follow up a recoiling opponent in melee. There are also more examples and rules clarifications, making the game even more accessible to newcomers.
Many of the special rules that were previously found in supplements have been included in the revised edition, along with some new ones (such as Legendary Shot and Rabble.) The text for the Swarm special rule is more detailed (as it had been clarified in FAQs and in Ganesha Games discussion group) and rules like Poison, Tailslap and Undead have been revised. The book also includes the point cost for the special rules, which I believe is a result of the game's mature state (i.e. point costs won't be changing a lot.)
In terms of presentation, the new book uses miniature photographs instead of diagrams. There are also more pictures although some of them are a bit pixellated. I didn't catch many typos during my first read and only one really noticeable mistake in the form of an unreadable table that was meant for randomly selecting a game scenario.
In my opinion, Song of Blades and Heroes is currently the best fantasy skirmish miniatures game, due to its balance between simplicity and support for customization. This revised edition makes it even more worthwhile due to the rules clarifications, examples and added content.
