Rocket Knight hearkens back to the days when nearly every videogame company had some sort of rodent, marsupial or other furry creature as a mascot. I'm going to miss old style 2D sprites, but I could definitely get used to this whole "2.5D" thing. It's a nice mix of old and new and gives the flat play area a nice visual pop. Artstyle is influenced by 16-bit sensibilities. Characters are bright with overly-exaggerated features and loaded with details. While Rocket Knight doesn't stand toe-to-toe with some of the 360's visual heavy-hitters, it ranks high when it comes to pure artistic merit.
Sound is nothing more than a collection of "videogames sounds," though they get the job done. After going back to the original games for research, I was surprised to hear how many of the original sounds are included. Quality is a little better, but hearing the old Konami "pause sound" is really cool.