Serious Eats - seriouseats.com

I think it depends - what kind of faux meat are you using?

With some of them it think it helps a little, but maybe not as much as with regular meat.

Yes! You can marinate meat substitutes. Press your tofu for awhile to get rid of excess water, then marinate for half an hour to an hour at most - it's great for baking that way. Tempeh is much better if you marinate it, because that can eliminate some of the off-flavors it can sometimes have. The best way to marinate tempeh is actually to simmer it in the marinade for about 20 minutes, then let cool and cook as planned (pan-frying or grilling are my favorites). Seitan also takes marinade very well - again, about half an hour is all the time you'll need.

The one caveat I'd have is about storebought seitan, which is often very salty, or any more-processed faux meat - marinades tend to be salty, and these products are already quite salt-heavy. So if you're marinating something that's already flavored, use a salt-free or -light marinade rather than, say, a shoyu-based marinade. With seitan, you can rinse a lot of the brine from the pieces, which will cut down on the salt level a bit.

Lots of great recipes can be found in the cookbook Veganomicon, or at the awesome site Vegan Menu (veganmenu.blogspot.com) - both incorporate marinades and sauces to make meat substitutes more satisfying. Good luck!

I had a great tempeh sate recipe I used back in my meat free days. It was actually good. Firm tofu will benefit from marinades and 101Cookbooks had a killer looking recipe recently with annatto which gives a slight nutty flavor and beautiful color.