Alright, I'll try to be helpful.
I'm assuming you're referring to Forum policies? I don't think much has changed really. Almost anything goes until it gets to the point that zultar/kestas believe it is harming the site. Is it vague? Yes, but honestly, I don't think it's really that hard to get a decent idea what is and isn't permissible.
I know this isn't exactly what you want, but let me try to explain the motivation behind avoiding clear rules:
First, if you draw a line, there are plenty of people that will spend all their time simply skirting the line, which is not what we want. What to do with those people? Continually move the line to the detriment of the whole site? No. Instead, we'd be forced to treat those people as special cases, which is what we do anyway, so we'd be back to square one.
Second, I think it is very hard to predict in a Forum like this what should and shouldn't be allowed. We have some simple ones, like no cheating, no porn, etc. At some point, though, we have to realize that we are accommodating such a wide variety of people from different cultures, religions, etc, that it would be very hard to make a list that we can always fall back on.
Instead, we have a fairly simple guideline: Moderate yourselves, but if you get too out of line, zul may come in and remind you to take it easy. Seems fine to me. Not sure what you think firm rules would benefit.