I prefer Sony's approach because while it may be more costly in the short term. In the long run they will be guaranteed a steady stream of exclusives and any other 3rd party exclusives they may pick up on the way is just icing on the cake so to speak.
MS strategy is fine as well but only if their console is doing very well. They were fortunate to have a 1 year head start with the 360 which allows them to use their current approach. If however they end up releasing their next console within a similar time frame as their competitors then I believe closing down and letting go of some of their best studios will come back to haunt them.







