On the other hand, I haven't yet had a job where written communication wasn't important from virtually day one. You may start out thinking, "Oh, I'm just going to code," but in reality you have to talk to clients (even if they're your coworkers), your bosses, prospective hires, etc., and this often takes the form of written communication. If you write unintelligibly to a customer or your CEO about why a feature is taking a while to implement, you're going to have a bad time. If you issue a poorly-worded question to a prospective hire, you'll muddy the waters in an already difficult decision. And there's no substitute for dodging the heat with a well-worded CYA email.
Learn to write precisely and concisely. Rhetoric classes, if your uni offers them, are a great investment.