From what I read, scrypt is (on paper) more secure than bcrypt, but it's pretty new so it's better to let it get time-tested and scrutinized first. However, is there any good, compelling reason to assume that it won't stand up to scrutiny?
Not yet. If there were any good, compelling, reason, cryptographers would already be warning people off of using it. Internally it uses SHA-1, which has shown weaknesses for collisions, but in password storage, the concern is more preimage attacks than weaknesses, and there are no indications SHA-1 will fall to preimage attacks in the foreseeable future. Scrypt is incredibly simple in structure, I doubt that any weakness would be found in it that would not actually be a weakness in SHA-1.