It makes that opinion more valid though. Imagine a site like Hardocp doing a review on hardware they have never tried. Would anyone take their review seriously. I think the answer would be no.
I'm not claiming to do a review firstly, and secondly, PhysX is a visual thing. Watching it in a video, or the real game will be no different, the same stuff's going on. Visually, the effects are going to be exactly the same, for example the Mafia 2 PhysX videos, it doesn't take playing the game to see that the effects are rubbish, if I played the game with PhysX on, I'd be seeing the exact same things.
The main problem with PhysX is that the effects aren't very good, and the fact that there are some ridiculous hardware requirements to run these effects. Crysis has some nice physics effects but it doesn't need a dedicated GPU to run them. PhysX is currently a scam and people who are easily convinced they're missing out are the ones falling for it and running out to spend their money on it quickly. The same people will also get angry at the mention of it being rubbish because they feel like you're calling their experience crap.
People like Coupe69 will have you think that I rabidly hate on anything nVidia related, it's simply not true. I'm not denying that I dislike nVidia, there are plenty of reasons, but my dislike for PhysX stems from before it was even owned by nVidia, my opinion is that nVidia have just dragged it down even more. I've always liked the idea of hardware accelerated physics, but PhysX has always been used in such a poor way. He'll probably also try to convince people I hate 3D vision too (becuase it's an nVidia tech of course

), I actually really enjoyed 3D Vision when I've tried it out. I think the effect is great, however it makes my eyes hurt after a while. I'd give it a try if it wasn't nVidia only, and didn't need 120Hz monitors, as I'm not in any hurry to replace my 3 Dell 2408s.
But then this is a problem with nVidia anyway, they like to keep things to themselves and try to lock their customers in to a "platform", clearly why they wanted to try to develop CPUs for desktop computers really.