Mesh is nearly ready for grid-wide release. I have the feeling it will be ready for residents before all residents are ready for it. Third Party viewer developers are working to get their viewers ready for mesh. There will be many residents in-world who, for a time, will not be using mesh capable viewers. At this stage of mesh development these residents will see only sphere, egg and pancake shapes instead of what the creators intended.
It seems to me Linden Lab could have some kind of place marker displayed in lieu of those mesh objects thereby letting those residents know why whatever they’re looking at seems rather, if you will pardon the expression, primitive.
There will be plenty of complaining once the dust settles, once Linden Lab has established and set the parameters for mesh upload. Some will find the upload cost too expensive. Many will find, free of the constraints of sculpted primitives, that it is all too easy to create an object with a prohibitively expensive number of vertices and triangles.
I have already read the complaints of people worrying that mesh will replace sculpts. Some had a hard enough time learning how to create sculpts and believe mesh far beyond their ability. The same can probably be said for the premier of sculpts themselves and I have no doubt there will be user-created tutorials with which to learn more about mesh creation.
I am learning more about it every day.