Does speaker toe-in affect reflection points?

It certainly changes the critical part of the reflection point, not only on the side walls but on the ceiling and the floor as well. Not a small thing, BTW, but often overlooked.

Remember when you are thinking about side wall reflections that the 'balance' of the radiation pattern is critical. Often the signal is hot on axis and more balanced off axis. Those speakers sound best either pointed straight ahead or having the axis cross in an identical degree of angle beyond the listening position. Only with the latter you will also minimize side wall reflection induced distortion, and lose some of the sense of artificially (room) created sound stage which relies on the side wall reflections for its presence. You might gain a very defined, pin point image, at least to the extent that your speakers allow.

With typical dynamic speakers in a small to medium size room I've found having the axis cross in front of the listeners head, to some degree, is preferable. Of course that is my sonic preference.

The first reflection location to the listener is always determined by the mirror. It a function only of the locations of the speaker driver, the wall, and your ear. For small changes in toe in, it essentially stays in the same location.

What changes as you adjust toe in is the intensity of the first reflection. It gets greater with toe out and less with toe in and has a maximum when the drivers are pointed directly at the reflection point.

What also changes with toe in is the direction of the speakers maximum intensity (generally perpendiclar to the drivers) and thus the locations of the resulting reflections as they travel around the room.

These changes can be significant and explain why such small adjustments can cause such a large change in the sound stage.

See: http://www.realtraps.com/art_room-setup.htm
Scroll down to Figure 4.

Zargon is right - it makes no difference in the reflection point. However, if your speaker has a fall off in response off axis (such as a horn) then the energy being reflected may be lower by as much as 3 to 6 db when toed-in.