How long does it take for a college to accept you?

It depends on whether or not this college has rolling admissions or if they announce all admission on April 1st.  If it is rolling admission, it will take them as long as they want to take. They may take a quick look at your new scores and decide or they may choose to wait to see if there are any other applicants who they feel would be a better fit for them before making a final decision on your application.  

A long time.  I've been buttering 'em up for 4 years, however, I still don't think they've fully accepted me.

New test scores?  Did you retake the SAT/ACT?  No way of telling. You could try skiing the admissions office if they can give you an idea of when is the latest you will hear back. 

It depends on the college. Some send decisions within a certain amount of time from the completion of your application; others will wait until they've made a decision on everyone who has applied. If the latter, the date is often in late March. 

Look at the admission website for the college in question. It will typically include an admissions timeline that will spell this out in detail for that specific school. 

You should have receive your notification information yesterday.