I run an animation studio and know first hand how many empty promises there are in this industry. I'm not defending these guys at all as they are scammers, no doubt. However, what I would recommend is that any potential investor needs to check out the studio and their client list, and even ask for references from the studio so that they can back up the studio's sales pitch. Find out what productions they've already successfully developed and how many shows they've produced. I've been in this business for 15 years and set up my own studio five years ago. I've experienced the bull**** that people come out with on a regular basis - especially people who claim to have the next 'big thing', and unless the idea is based on an already established product (eg. a book) then your chances of securing a deal are pretty slim - even with an established product you're up against a lot of competitors.
I have an investor wanting to invest in my studio, but the reality is that up until this point we've had nothing to invest in - and that's my opinion, not theirs - so I've put any negotiations with them on hold until I feel that we have a project worthy of investing. At this point I think we're there, so I'd be interested to see what they come up with.
In conclusion, don't believe the hype. Use sites like LinkedIn to see who they're connected to and why, and do a bit of behind-the-scenes research before you commit to anything.