I said the exact same thing in this post about a month ago //www.curezone.org/forums/am.asp?i=2117165#i.
The Human Microbiome Project has shown that Bacteroides is the most prevalent bacterial genus in the gut, and the only probiotic that I know of that offers it is Prescript-Assist. Dvjorge is right that a Fecal Transplant
is currently the only way to get ALL of the hundreds of species of bacteria back into the gut, but I tend to believe that within the next decade, all of these species will be identified and cultured in the laboratory without the need for "poop".
Another interesting point is that the gut microbiome does vary from person to person, according to their age, geography, ethnicity, etc. So it would seem even more likely in the future that each person could have a personalized probiotic to match their natural gut microbiotic make-up.
Viewed in that light, the idea of "Lactobacillus acidophilus" for all seems as backward as bleeding a wound. As I mentioned before, Lactobacillus only dominates the vagina.