Silver's sprite, I think it is the same as his art, it's just too dark to blurry to see it pants are blue.
I just noticed something, the new dex system, the one where you can see the pokemon icons when searching through the dex, it has the same numbering as G/S (Togepi no. 46, Ekans no. 50, Arbok no. 51, etc) which means that all 1st gen/2nd gen (except starters and legends) are in the regional dex.
Something else, I think that the towns/cities will be like their G/S ancestors and will be different colored, Goldenrod City looks very golden, Newbark is green, Ecruteck is Brown, Cherrygrove is pink/magenta, Violet City is Violet, and I can't tell the others cause we can't really see them, (Like Violet City, its looks like it has 2 houses and thats it!)
It also looks like the gyms are different colored too, I can see Voilet Cities gym and it has blue on it, Goldenrod's has white and Ecruteck has purple, and Mahogany has a greeny blue color on it, if this is true, then its about time they made the gyms look different from each other!
As for that unknown pokemon by the Steelix pic, to me it looks like Wurmple, but it can't be so I think its Hoothoot or Sentret, its looks brown.
And do you reckon the HGSS site will update with all these pics, so we can see them, cause they didn't put up some of the last months pics up.