Generally speaking, when a new feature interferes with existing functionality, it is preferable to default to the previous behavior. In that way, the folks who requested the new behavior can go in search of, and enable it, rather than the vast majority of folks being affected.
This really needs an easier-to-reach toggle. In general I prefer the new method, but sometimes (like when drawing a triangle with an odd number of pixels on its base) I need to be able to drop a point in between pixels and let Photoshop antialias. A checkbox in the tool bar would be fine, instead of having to go into the prefs window.