OP includes video editing in his requirements.. On that aspect, the quad core easily outpaces the dual core.. Further, they are equally clocked.. Thus, dual core being a minimum requirement for gaming nowadays, the quad easily wins the verdict.. Both CPU's can (and will) get bottlenecked easily for a dual or more video card setup depending on the cards.. Overclocking to the rescue then and this is the only aspect on which the i3 530 may edge out the X4..
The only thing you forgot was that the i3 is faster at a given clockspeed per core. Equally clocked does not mean equally performing per core. Otherwise I agree.