Do you use any colour correction?
Also, sorry to sound like a noob... But what is motion blur faking?

Basically, what happens with computer-generated content is the fact that you don't have motion blur. A real camera lens is always open, capturing the image, but in the Source Engine, it's like if you had a camera that opened its lens for a nanosecond, captured the image, then closed, and this goes on for every frame.
There are two solutions to fake motion blur;
1) Capture your game at 500 fps, then merge all the frames together. I don't do this.
2) Capture your game at whatever frame-rate you want (I use 50, personally, so the software can still detect the vectors properly), then use a vector-based motion blur detection. It takes quite long, though, so I skip that part when clips don't need it. And I never ever use it if the clip gets used for chroma keying, as not having motion blur is actually a strength when performing incrustation.
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About the color correction, I use it a lot, to reproduce the look of real movies; I haven't uploaded any comparisons since September but there are still
these two.
Here's my effect pipeline: Image -> Cropping and Panning -> Clip-specific effects -> Master effects
The most important part of my CC pipeline is to create a... well, bloom. It's meant to erase hard edges and soften everything up. After that, I apply soft contrast, which cancels the muddiness of the image, then applies vignetting (nowadays I really make vignetting less intrusive though). The versions of the effects located at the end of the chain make everything warmer.
The abandoned concept for Chapter 4 (the first few seconds) actually used this pipeline TWICE. The normal pipeline is integrated at the end of the global effect chain, but I made the image cooler (as in, cold) by applying a different variation of the same effect before the former. What's quite cool (pun unintended) is the fact that, even if I make the clip colder, the end of the chain will always modify that, so it doesn't look bad. It's a bit hard to explain.
Gosh, I sound confusing.
Any more questions?