I've been at my current employer for a little over 4 years. Our vacation policy is 1 week your first year, 2 weeks in year 2-4, starting your 5th year you get 3 weeks and starting your 15th year you get 4 weeks.
Our office is closed 11 days a year for holidays. New Years Day, Presidents Day, Good Friday, Memorial Day, 4th of July, Labor Day, 2 days for Thanksgiving, 2 Days for Xmas, New Years Eve
Being a relatively small company ($40 million-ish in revenue) most of the salaried, college educated people are older and have cut their teeth in larger companies and have lots of experience, so if they're smart they'll negotiate for 3 weeks to start. I was one of the very few who was hired as an unexperienced college grad....so I didn't have that much leverage and had to pay my dues. Most people try and get 4 weeks but it's difficult to take 4 weeks of vacation in a small company because most of the time you're the only one who can do your work and if you take too much time off you'll always be trying to catch up.
If I have a doctors or dentist appointment I try and schedule them first thing in the AM or last appointment of the day just let someone know and get to work when I get to work...i've never gotten any flack (because i don't abuse it)
I think our official sick day policy is 6 days a year, I don't know if my boss keeps up with it on my end because I've only missed 1 day in my tenure here and the only reason I missed that is because it was swine flu season and I was running a little fever and thought I may be coming down with the swine flu and we were under strict instructions not to come to work if we felt the slightest bit under the weather, it was a false alarm so I was at the office the next day.
As far as how I take my days off. I usually take 4-5 days straight for a vacation in the summer and then use the rest on long weekends (1-2 days off)