Exactly How Important Is The Quality Of My Degree (Grades, GPA)?
Of course, it's no problem to tell people "Hey, I was lazy in school but I'll work super-hard for you." Unfortunately, people won't buy it.

From my time in the software industry, hiring quite a few people, I would actually not normally even look at their grades, unless they were borderline in the interview. Even then, if there was another candidate who was better in the interview, that borderline candidate would not even get a callback.

Some people will care about grades but for computer science 'guys' I find that what most people in industry really care about is what you can do for them. Can you help them more than someone else can help them? If so, then you'll likely land a job.

If you shape up, pull out of your 'funk' and get down to actually learning, you will likely be OK. If you let depression pull you under water, you'll drown. 

You've started your degree, you should finish it. However, don't let the past dictate your future. This is the first day of the rest of your life. It's always darkest before the dawn. I'm sure there are more sayings along this line but in the end, depending your area of IT, you can do fine even if you had a bad start to school. If you have a strong finish, it's easy to explain that you should be judged on your 'exit velocity' rather than the start.