The oleophobic coating works and works well. I don't have anything on the screen of my 4S and very very rarely need to clean fingerprints off it at all, whereas a colleague has a protector on his and is forever cleaning it as it gets so covered in muck.
I really don't get screen protectors on modern kit as the glass is so tough that anything that's going to scratch it will go through a protector like a hot knife through butter.
I am tempted to remove my screen protector on my iphone 4, have the power support anti glare on there now, figured that would get more chances of being banged around, even when I'm careful where and what pocket I put it in, but, it does dampen the screen clarity, due to the anti glare portion, but, I think I'll just take that rascal off right now haha, you guys talked me into it, that plus it's my company's phone so if something untoward happens to it, the onus is on them and not me to get a replacement... ;)
Edited to add that while this isn't the iphone forum, just took off the Power Support Anti Glare and WOW, MAN is that one lovely display!!! photos really POP now and that coating does seem to keep the fingerprints down a lot...