I'm still hoping for a new Mega Man X title with 16-Bit style graphics. I'm hoping for something like that ever since Mega Man 9 was announced. =/
The team decided that striving for an extended sense of nostalgia seemed a bit off from what gamers were looking for, and decided to use new graphics to show that not only is Mega Man back, but also improved.
I'm sure it will be the same for X as well, not to mention brand new designs for X,Zero and Axel already shown and 16bit would do them no justice.