I think it sounds freakin' cool!
The backstory looks pretty well thought out, and the portal to another universe idea is neat. DelToro has a gift for taking the fantastic and making it look like it could be taking place in the real world. If I had to choose someone to create a believable depiction of Giant Robot VS Monster action, he'd be the guy.
Del Toro is such a sci-fi fantasy nerd I agree with you, we're lucky to have someone with those kinds of hardcore passions who happens to be a very good filmmaker at the same time.
A lot of people dump on the Hellboy films, esp the 2nd one and from a mainstream, commerical POV, I can sort of see where they're coming from, but as a comic book reader, I can tell both those films were a real labor of love from GDT and think he'll do a great job making this upcoming film, even if it's not exactly everyone will like.