We investigate how DNA sequence, ATP-dependent chromatin remodeling and 
nucleosome-depleted 'barriers' co-operate to determine the kinetics of 
nucleosome organization, in a stochastic model of nucleosome positioning and 
dynamics. We find that 'statistical' positioning of nucleosomes against 
'barriers', hypothesized to control chromatin structure near transcription start 
sites, requires active remodeling and therefore cannot be described using 
equilibrium statistical mechanics. We show that, unlike steady-state occupancy, 
DNA site exposure kinetics near a barrier is dominated by DNA sequence rather 
than by proximity to the barrier itself. The timescale for formation of 
positioning patterns near barriers is proportional to the timescale for active 
nucleosome eviction. We also show that there are strong gene-to-gene variations 
in nucleosome positioning near barriers, which are eliminated by averaging over 
many genes. Our results suggest that measurement of nucleosome kinetics can 
reveal information about sequence-dependent regulation that is not apparent in 
steady-state nucleosome occupancy.