<i>OK, maybe I am clueless, so don't jump on me yet... But who says future EMDs won't be needed or wanted?</i>
I suppose if EMD was a cash cow for GM, they'd hang on, not sell them.
<i> It also just seems to me that having a SINGLE large supplier without competition would be a disadvantage to the railroads in terms of the price and quality of what will be offered.</i>
So what? Most US stuff, at least passenger, is so customized that it ends up being single supplier anyway.
<i> As far as I can see, competition with EMD was a major part of what brought GE's locomotives so far forward. </i>
Neither are exactly leaders in the industry technologywise. From what I've heard, a lot of what was keeping EMD alive was overseas orders, and the Europeans have been either progressing quickly with their own designs, or phasing out the applications where EMD's stuff was competitive.
<i> Unless I'm mistaken, there haven't been any companies other than EMD and GE who have been able to get a strong foothold on the mainline freight locomotive market in recent years.</i>
Alstom, Bombardier, SLM, Seimens, and a few others I can't think of right now. The first two already have a foothold in the US market.
<i> Will another company be able to take EMD's place should they disappear? </i>
Maybe. It's a function of the size of the order being large enough to recover the costs on a product that's unmarketable virtually anywhere else. If any foreign firm can make money on US freight locomotive manufacturing, they will enter. Otherwise, GE will be it and the industry will be faced with either adopting modified versions of European designs, or paying GE's premium for whatever GE feels like making.
It's sure a boost for GE. But the industry could always walk away from GE...
<i>
(If I'm totally wrong with all of this, I'll back out and won't meddle any more with this.)</i>
No no, keep asking questions. It's only by asking questions that you learn. :D