Things I like about the new book:
-the little ribbony bookmark.
Things I don't like about the new book:
-the smell of the pages. Basically, I wish all GW publications smelled like the soft-cover codices/army books. I don't know if it's just nostalgia (the smell takes me straight back to my local game store in country Australia ca 1996), but I can't fail to get excited every time I open a book that smells like that.
Has any of the rumours said anything about multiple charges gone?
I just noticed as i read through the rules that you can only charge ONE unit now. This will be very interesting. I keep thinking that tyranids will benefit from this.
Multiple charges are still in (page 27), but like Sig said, you don't get the attack bonus. There are also some additional bits about "primary" and "secondary" targets. I'm not sure what concrete differences these things make, but I imagine there were ways of "gaming" the way the 5th ed rules were expressed or something that is no longer possible.