Now this is my kind of work style. I do similar: when the door is closed and music has changed (though it varies by mood), I’m zoned in to whatever I’m working on. Most times though, everything can be nice and open, and I can stop for chats and interruptions.
Basically, I’ve got two modes of work: loose/open, and focused/closed. When I’m in "open" mode, my instant messenger status is set to available, I’m surfing, writing, checking email, coding, listening to music with lyrics—getting things done, but in a multitasking way, open to interruptions and tangents.