The primary difference is the type of switch used for the keys. This uses the "Razer Green" mechanical switch, which is actually a version of Blue made by Greetech and re-branded by Razer. It has a slightly shorter actuation distance and total travel distance compared to the original Cherry MX Blue switch, which makes it slightly more responsive and better feeling, imo.
The Ornata keyboards use an interesting switch type that is a combination of membrane dome and scissor. It's essentially a switch that provides a feeling similar to a mechanical switch while being far less expensive to produce. Personally, I like the feeling of a real mechanical switch better, but you may find the feel of the Ornata switch to suit you just fine.