It seems that soon we will have some new looks for the Second Life client. One is done by Benjamin Linden and thus will replace the existing look of today at some point and the other is the OnRez viewer which will debut on Wednesday in conjunction with the airing of the CSI:NY episode about Second Life.
So here are the two screenshots:
Linden Lab viewer
(The long term goal here is btw to make the official client more easily skinnable in general)