i imagine the search functionality could/would be a mess given the immense number of people involved in productions.
the key feature of MangaUpdates i want is the "tags/categories" system—i pretty much only ever find new manga via tag searching and never* through "genre," which is the standard (and appears to be the only) way movie sites i've seen work. genres are just so vast and hardly granular enough to really be useful.
am i missing anything? a brief survey didn't turn up much, although I was on my computer browser and there seemed to potentially be some tracking apps.
note: the tags should be community-applied-and-voted, not just things you can use on personal lists
*note:
Spoiler (mouse over to view)
except to eliminate the more *clears throat* adult genres