Having had both phones, I can provide the following information based on my experience. The Inc's camera produces sharper looking images. This is mostly noticeable when you zoom in to a photo or view it at native 8mp resolution. I have noticed this in my own use with both phones and it has been proven online in articles discussing the issue.
The above link is just one of the comparison articles I have read; a Google search will bring up several others. Every comparison seems to follow what I have found using both devices, with the Inc camera taking sharper photos. Also, as stated above the Inc seems to oversaturated images giving them an unnatural overly vibrant color tone. I personally like this about the Inc, but others use it as a negative. It's really personal preference and as you said, it’s easily fixed in Lightroom or Photoshop. Unfortunately, the clarity issue does not fix so easily. Having run Droid X photos through sharpen in Photoshop I can fix part of the clarity issues, but they still don’t look as sharp as the ones taken on the Inc.
This is not to say the Inc has a "better" camera then the Droid X, in fact comparing hardware specs the Droid X is technically superior. The hardware shutter and two stop photo button functions like a regular point and shoot camera. The Inc however is still a "cell phone camera" in the way it functions. The Droid X takes photos faster than the Inc due to the fact the camera focuses faster than it does on the Inc. Overall the Droid X camera feels and functions more natural; like a point and shoot camera. I am not sure if a software update can fix the clarity issue, but if it does the Droid X camera would be superior in every way. Even with the clarity issue, I would have to say the Droid X camera would by my choice between the two phones.
With regard to video I have not taken 720p on the Inc as it was not an option when I owned the phone, and the one in the box needs to be activated before it will let me do anything which is not going to happen. The Droid X takes great video, in fact it seems to be clearer then my point and shoot which also does 720p. Where it is not superior then my standalone camera is frame rate, which is limited to 24fps instead of 30fps. This is noticeable when you pan the phone while taking video or have a fast moving subject. I am not sure if this can be fixed via a software update or if it’s a limit in the device technology.
Just returned X to Verizon.
Bought it full price and paid $35 restocking fee - I look at is as "rent" while I played with it and tried to make a decision.
Reasons for Incredible over the X as previously mentioned.
I'll miss the Panoramic photos and the voice clarity.
Looking forward to the next generation of Droids (not the D2 but whatever follows).