On the off chance you stopped by because you found me on #
Beta-Readers or somewhere editing related, here are some helpful links to places you can get critiques~!
On DeviantArt
DA is fortunate to have a number of groups dedicated to bettering your writing. This list is not definitive there are many more groups out there, this is just my pick of a few:
#Beta-Readers is a service where writers are paired with beta readers via a system of matching criteria. The group works hard to pair authors and betas with the most compatibility and from my experience, they do a good job. If you're looking for a long-term partner in either writing or reviewing, you should take these guys up (or
look through some public profiles).

If you write scripts of any kind,
#House-of-Playwrights has a
WIP folder for critiques. Though you have to critique others and outline questions you have for your own work, it's a good place for script-specific feedback.
#WritersInk, which is an outstanding community by the way, has started hosting
"critique night chat" events which focus on a few pieces in a very warm, workshop-like environment. It may be better for those who wish to critique rather than be critiqued, but it's still a good place.
#AnotherContestGroup isn't critique-specific, but a number of times I have come across critique contests, so it gets a mention.
Elsewhere
If you want to get some different eyes or need some very specific audiences, a few forums/blogs/offsite groups offer their services:
PeerEdit is a small blog run by one or two people who take critique requests and edits in separate posts. Often you'll get a more eye-friendly version of pointing out errors (while DA comments is a little lacking in formatting) with some good feedback. While the site encourages optimistic and constructive criticism, you may be adverse to their grading system or to having unknown people look over your work, which is always a valid concern.
Lemma Soft Forums is pretty much the largest gathering of English language visual novel creators and they have a
subsection specifically for writing advice. If you're creating a VN or dating sim, you can always use this place for short critiques or advice.
Editorial Anonymous dishes out advice to those who email the site admin. It's not entirely for hobbyists, but a good source of near-professional opinions and advice.

Sometimes the people at
Writer Leopard Advice (or those who follow them) accept pieces for critique. The blog itself is more advice for writing, and sometimes they're incorrect about details, but their hearts are in the right place and they're willing to help writers.
(You should totally support these things)