| Well the first difference that springs to mind is reality. School is far from it, and when you move to a large city with a real scene, it hits you in the face like a mac truck doing a buck. ("artic lorry doing a ton" for my english readers).
In school you are more relaxed and can spend more time shedding, hanging, meeting people, working your sound out, preparing etc.... and then you get to New York or LA for instance... and it's all systems survival.
Sometimes I wish I had never been in school at all for so many reasons, but it was a nice few semesters to be inspired by people of my own age and younger, and to check out music I had never been exposed to before. It was a huge influence on how I play today. Just opening my ears to everything that was going on in Berklee. All my peers were fully fledged jazz musicians as far as I was concerned. They had certainly spent more time studying their craft that I had up until that point, and they were really starting to create their own voice as writers and players. I had none of that together when I got there, and so started a time of the most intense shedding I've ever done.
I would be up in the am to shed, go to whatever classes I had in my schedule (or not, I did just not go to school a lot! just to stay home and finish a transcription), and then it would be shed, sessions, home to shed some more, stay up more of the night listening, grab a few hours sleep, and then do the whole thing again.
There was no excuse then, and no excuse now for me when it came to working at what I loved. It was at the forfront of my thoughts always.
Now there wasn't really much change when I left school and turned pro so to speak. I never had any gigs when I first moved to NYC so I would spend most of my days home shedding 6 or 7 hours a day, and then playing video games way into the night with a group of musicians who had a love for James Bond Goldeneye for the Nintendo 64. it was about the most human I managed to get in that period as I felt there was still so much work that needed to be done to my playing.
Also, playing videos games was cheap. And when you have no money and no gigs to make money, you need a cheap passtime.
So the main differences between the school and the scene thing for me were the fact that in school it was all contained. It was laid out on a plate for you, with people milling around everywhere you looked. In the city it was different because every has their own thing to deal with, and really won't give you much time of day unless you really push it. So to network in a city like New York is a tough one.
You have to switch your brain to a different wave length to find inspiration in a very immediate sense. You go to more gigs in the real world than you do go to classes to meet people. And then you have to find the constant influx of players that are graduating from music school and moving to a major city to make it. Drawing upon their energy can keep you in that young and fresh frame of mind for wanting to find new things.
If there's anything you think I missed, drop me another line.
Easy,
Janek | 
