Kris has stated on his Twitter feed that he will be releasing a 64-bit version "soon" due to the App Store requirements. He's also indicated that that will be the only real change to Marvin for that release.
He has mostly moved his development efforts to Gerty (his journaling, scrolling reader) and his new email project. He has "plans" for Marvin 3.0 but has basically said it's not under development and he has no time frame on when he'll even start.
He will respond on Twitter but has abandoned this forum. The iOS Reader App connection to Calibre should also be considered dead - the library (despite ShellShock's yeoman efforts) has issues and Philantrop was more of a maintainer of the plugin than a hard-core developer (the original developer abandoned it over a year ago).
Accept the fact that Marvin is what it will be for a while (stuck badge and all) and that if you want to connect to Calibre to do it via its OPDS feed and you'll be happier. Marvin is still a great reading app, minor warts and all.
If people are still using Stanza, I think we can use Marvin for a few more years.
