Veteran DK Viner, here!
DK Vine may have a certain reputation as an old stinkhole where jaded Donkey Kong fans go to bitch & moan, but, as is typical of the hyperbole of the internet, that's a poor generalization of what is actually a very warm and good-humored community.
To me, personally, DK Vine has always held a very special place in my heart; it was one of the first online circles I ever joined (circa 2007, if I'm not mistaken -- I distinctly remember finding the place on the same day that Diddy Kong was announced for Smash Bros. Brawl), and I've come to feel very sentimental about the site in years since. As one of the few still-thriving relics from the early days of online fandom (as far as I know, at least), it sort of represents the "old days" of the internet for me, as well as some of my first exposure to internet culture. In short, DK Vine is very close to my heart for a number of reasons.
Anyway, my own nostalgia-ridden thoughts aside... Assuming you're planning on signing up, I'd definitely say the old 'Vine's still worth joining today. While the site's vast inside jokes and nearly-two-decades of history can be intimidating to newcomers, it's been proven time and time again that new members can nudge their way into the fray if they click with the community well enough. Most of the folks there are really knowledgeable, friendly, and perfectly literate (thank the stars!) -- the community seems to strongly attract people of this sort, fortunately. Some forumgoers are a little more crotchety than others coughplanetcoolcough, but they're usually put in their place very quickly if something dumb slips out of their mouth.
I think the only piece of "advice" I'd give to you or anyone else planning on joining the site is this: DK Vine generally likes people with a good sense of humor. If you have a sense of humor about yourself and others, you'll probably settle in better than if you were a tightwad who can't take a joke. You'll come to find that this is an essential element of DK Vine culture.
