this blog post by pretendo details what happens next for them, reveals a way for unmodded Wii U systems to use Pretendo with a DNS change and some limitations, and announces official (as in, with the blessing of the developers) support of Colors! 3D.
as for me, my 3DS and Wii U will switch to Pretendo full-time, like i bet most of you are. My 3DS Pretendo Friend Code is 4176-7853-8075 and on Wii U, my Pretendo Network ID is Obspogon. Please add me there and comment with your codes (your PRETENDO codes, which are different from your Nintendo codes) so that we have more people to play with.
for now, submit your remaining network and spotpass dumps to the pretendo discord, update your nimbus and inkay patches, build up your pretendo freinds, and we'll see each other soon.