I don't get this comparison at all. To me, the big deal with something like Beta vs VHS is that once you make a purchase, you're committed to a format. That isn't the case here. The manufactures, I suppose, could see it this way because they have to commit quite a bit of their resources to produce one type or the other, but to the consumer it doesn't matter.
If, rich bastard that you are, you invest in a whopping big plasma TV now, and find that it doesn't suit your needs in a few years, you're not going to feel like you're stuck using plasma TVs. You'll buy the TV that suits your needs... it won't be like you've got dozens of Beta tapes sitting around to influence your decision.