I'm just testing markup in mail and it seems really really good. Admittedly I haven't played around with it in detail but a few photos I've tested and just roughly sketched an arrow, speech bubble etc just works beautifully and the fact it all works directly within mail is very cool. Can't quite figure out how to work the signature option though, I've had no luck with that feature. I'm also really liking the new look of Yosemite, I want iOS to look more like this. Anyone else's thoughts on Mail markup?