All this talk about using 2 bookshelf speakers as one virtual center channel has me thinking. Why isnt this a more discussed option in the HT community? It has the potential to:

1 - offer a more dispersed, smooth center channel signal (toe in, toe out options, one above and one below TV, etc)
2 - often cheaper than dedicated center
3 - significantly lower frequency response opportunity (in case of M3 vs VP150, at least)
4 - 4 ohm impedance (assuming wired in parallel) vs 6 ohms meaning more output (wattage), (a good thing if your receiver can handle the load)
5 - Sounds like a cool idea

There may be others as well. Would like to hear the downsides as you guys see them. I havent made a center channel purchase yet, and think this one needs to more exploring. TonyM made me start thinking about this - lets pick up from there! Thanks Guys, Jeff