I also think that Sasuke has a higher form of Mangekyou.
Like yondaime said a Normal Mangekyou is formed from 3 Tomoe = 3 point Mangekyou. Itachi, Madara's first Mangekyou, Madara's Brother, Kakashi all have a 3 point Mangekyou.
When Madara obtained his brother's eye, the appearance of the Mangekyou that is formed is a 6 point Mangekyou (Combination of Madara's Mangekyou and his brother's).
Sasuke (from his MS appearance) have a 6 point Mangekyou.
3 point Mangekyou = Normal Form of Mangekyou Sharingan
6 point Mangekyou = Higher Form of Mangekyou Sharingan
Well, just a thought...
For the record, when I saw the Sasuke's Mangekyou on the spoiler pics, I thought "what the heck", a FLOWER MANGEKYOU SHARINGAN!