In all of the cases I had to do this, I was the only company employee working from home, so you have to take some extra precautions. People at the home office will joke and ask if you're in your bathrobe watching TV. They'll get over it as you demonstrate an ability to get things done for them.
Make sure everyone is aware of any time difference due to time zone and/or a flexible schedule. They won't always get this right at first. Expect calls at some strange times but remind them you are on a different schedule.
If you're not doing it already, get use to not printing things out to paper. Sometimes this gets too convenient when you have the super laser copier in the office. The photo inkjet home printer is slower and much more expensive (If it weren't for airplane boarding passes, I'd get rid of mine.).
Beware of the temptation to take on too many home duties/chores/honey do's etc. You may have saved time off of your commute, but now you'll have to make a special trip to the cleaners instead of just stopping after work. There still are weekends.
Keep up the communication and let people know where things stand. You don't have all those little meetings around the coffee pot. Take the time to call people up and ask how they are doing to maintain the social goodwill you built up. And if you didn't build any, get started. If you have a problem with your pay check, you want the payroll people to recognize that it is a human being that needs their money to pay bills and not some 'computer guy' they've never met.