Marian was put on ice, or abandoned, or dunno. Chances that it'll be released at all are pretty low from what I've seen around the tubez. (
An example)
Same thing for Aquaria2, with the difference that it wasn't even started. The attitude a la "there might be a sequel one day, but there are no plans to actually make one" hasn't changed over the last years.
... So we're now making a sequel mod ourselves, here:
http://www.bit-blot.com/forum/index.php?topic=4349