What’s the state of the art in probiotics?

obsessivewoman is on antibiotics to kill off her sinus infection, so I figured I should check up on the state of the art of probiotics so she could reload her gut bacteria from a known good state. In the days of yore, I would’ve just picked up some yoghurt with a live Lactobacillus acidophilus culture, but there are half a dozen brands of probiotics in the dairy aisle at Safeway:

• Activia is a Danone product with Bifidus regularis, which claims to help with regularity.
• DanActive is another Danone product, this time with the DN114-001 strain of Lactobacillus casei that purports to boost immune function.
• GoodBelly is a line of fruit-based probiotic drinks using the 299v strain of Lactobacillus plantarum, purporting to help with digestive upset. (divertimento, you might find this a good way to evade allergies.)
• YoPlus is a yoghurt product from Yoplait, using Bifidobacterium like Activia.
• Eating Right probiotics aren’t even on Safeway’s own web site, and their brand name makes them rather difficult to look up online; I can’t even find what bacterium they’re using.
• Lifeway Kefir is a dairy drink with a cocktail of critters: Lactobacillus lactis, rhamnosus, acidophilus, plantarum, and casei; Bifidobacterium longum and breve; Streptococcus diacetylactis, Leuconostoc cremoris, and Saccharomyces florentinus.

Bifidobacteriumanimalis.com notes that a lawsuit has been filed against Danone for misleading claims, but that there is no further data. Food-info offers advice on selecting probiotics. Probiotics: Hope or Hype? summarizes findings from a review published in the Journal of the American Dietetic Association early last year, and provides a chart (PDF) of those found to have beneficial effect.