Ok, some constructive criticism:
I don't care what anyone else says about this, but this was good! Very good. I very much liked the art style employed here, it added to that cartoonish style of the video. The expressions used matched the point of said "goofiness". The bat crayon part was funny, and I am sure others have mentioned the timing. I personally believe the timing was perfect, and the delivery could have been a bit better. you know, the over the top presentation effect. I love how you took one of the most manly, serious heroes and made him look...well...flat out funny (in a good way I mean). The dark knight is pretty good at makin us laugh.
As for the BGM, I found it pretty fitting. I found the contrast between the mood of the short and the ambience of the music pretty fitting, even if it was only for a few seconds. The Voice acting was nice, but could be a bit "smoother", know what I mean? However, it was still of very good quality. The length of the flash was decent, but I felt as if it dragged on very slightly, but it was still fun to watch through and through.
You have amazing talent, and I hope to see more of this! Keep doing what your doing, it is working very nicely!
With that, my 10-5 is well placed.