The first "scans" from CoroCoro have arrived and it confirms Shaymin's Sky Forme as well as provides smaller stuff regarding Platinum. At the moment the scans are way too small to get any info or decent pictures from, however there will be more scans in the coming week. However, it does seem to hint that the RS Regis are now obtainable within Platinum.
The blue skY blog has managed to get some further information from the scans despite the size. Aside from the Regis noted above (which can only be obtained with Movie Regigigas it seems, it is unknown if this will change outside of Japan), there are two new characters to be input in the game, their names and purpose are not yet known. There's a new area called the Torn World, and Shaymin's Sky Forme is Grass/Flying and weighs in at 0.4m and 5.4kg. We'll bring more as bigger scans arrive. Below are the scans.
Source: www.serebii.net
I love the new Dawn look, and I am very interest in the new characters.
Edit: the info and pics are from the new pokemon platinum for DS.
