How to round values of a Float List in Animation Nodes? Math node only has Floor and Ceiling modes, while Float to Integer or Round nodes don't work with Float List (sockets doesn't connect in v2.1 (for 2.79b). Am I missing something here?

Making a Loop just to accomplish rounding seems to be overcomlicated for this task.
Adding 0.5 before flooring gives you rounding. Alternatively, subtracting 0.5 before ceiling gives you rounding.