Really depends on a number of things. If you lay your bike up for the winter, then many of these maint issues can be taken care of then (like the fork and radiator). Brake stuff should not wait, but since my brakes were working perfectly, I decided to wait until this winter's layup (in about two months) to really go over the brakes. I'll change oil and brake/clutch fluids then, too. And probably a project or two (like a Race Tech rear shock). If you ride year round, then you might as well do everything now.
These are just our opinions. Your predilection towards preventative maintenance will determine how much time you want to spend working on the bike now.
[h=3][/h]