So there are many, many carriers out there that seem to do the same thing. The category of baby carrier is "soft structured carrier." These wonders claim to be good from about 15 to 40 pounds, and you can wear them front or back, and some can even go onto the side with some strap switching (which I have never tried, but my sister-in-law seems to enjoy using her Ergo this way).
The difference between a soft structured carrier and a Mei Tai is that these carriers have buckles and snaps instead of longer straps and knots. They also seem to have wider and more firm padding at the waist, but I don't see why you couldn't make a Mei Tai this way.
The different soft structured carriers all seem to be slightly different than each other.
The Ergo is quite popular where we live (Berkeley, CA). It has a sleeping hood and a great big pocket in front with two parts-- one with a zipper and one to tuck things into. It comes in organic and regular cotton, and also a "sport" model, which seems to be lighter weight material for hot days. I love my Ergo. The pocket is just the right size for a change of pants, my phone, a packet of tissues, my wallet, and a few snacks. Unfortunately, I have washed the Ergo many times and the waistband foam is not that supportive anymore, and it has lost some of its oomph.
I was thinking of buying a new Ergo and re-selling my old one (they hold their value quite nicely-- used ones go for $40 to $60). I got distracted online and found the Boba carrier. It is also a USA product (Ergo is from Hawaii and Boba is from Boulder, CO). It has a detachable hood that snaps onto the straps just like the Ergo. Its buckles are like the Ergo's, except the waist strap buckles in the back instead of on one side. The buckles and snaps feel heavier and sturdier than the Ergo's, but maybe it is newer. It is missing the pocket, but it is kind of nice not to have it in the middle of the carrier. But I do enjoy having somewhere for my essentials without needing to carry an additional bag. The Boba has foot straps for the baby-- they hang off the waist and are like stirrups, supposedly allowing for the child to ride in more comfort. I can't get my child to keep them on for more than about half of a block, but maybe he is just used to traveling in an Ergo or Mei Tai.
Overall, I am ok with both carriers. I like that the Boba feels sturdier-- the cotton and the straps and buckles and snaps just feel more substantial than the ones on the Ergo. But I miss the pocket of the Ergo when I use the Boba. For that reason, I am going to recommend the Ergo over the Boba.
Note posted much later: I recently got the new Boba, the Boba 3G and LOVE it. Read more here.