http://lists.opensuse.org/opensuse-artwork/2014-07/msg00013.html
Hi all.
After working on the Artwork for the upcoming release for a while now, I would like to suggest the following:
Just change the wallpaper in 13.2, leave the rest as-is. The wallpaper should play well with the existing plasma theme, like the one I recently posted.
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If you do not agree with this plan, please let me know in which areas you are planning to help. This means not ‘just another wallpaper proposal’, which is of course fine, but help on the plasma theme, kdm / ksplash / plymouth / colors / gtk / icons …
Just thought I would post this here for those of you that don’t read the mailing lists. 13.2 is almost here but there havent been too many theme proposals made on the mailing list. If you have any experience with this or know someone that does, this is a great chance to get involved. Personally I am not very artistic but I plan on spending some part of the weekend trying to contribute. 
So are they looking for wallpaper submissions or entire themes?
Sorry for the delayed reply.
Both I guess, but if you were to make a theme it would really take some dedication as it has to make sense with the wallpaper and possibly other themes (plasma theme + application colour scheme + icons + window decoration) which all have to work together. That is probably why there have not been many theme submissions so far.
From what I have read it looks like they might change the colour scheme and possibly add a new icon theme sometime in the future. There is also some work being done on the installer theme so we will probably see new things by 13.3. However as I mentioned before it needs to have some unifying aspect that makes the themes fit together and that is difficult when there are not enough people contributing (Sadly I am guilty of this). This is simply my understanding of the situation, the reality may be different.
As far as wallpapers go they are always looking for those so submit some if you have any