I preferred the MacPorts model, but when I used them both, there seemed to be a lot less support compared to Homebrew. When builds stop working, they seemed to be fixed in Homebrew before they were fixed in MacPorts, and Homebrew also seemed to have more current versions of most packages available.
Every time "boost" updates, you're stuck recompiling half your ports for the next 20 minutes to use the new library. With Brew, you wait a minute for the new packages to download, and you're done.
I never know what to make of "people still use ______?!" comments
Usually people are assuming a network-effect that would make using not-Foo when Foo has "won" problematic. Like, imagine using MySpace as your social network today. It'd be a ghost town and nobody you knew would be on it.
In this case, I imagine people would expect that MacPorts either wouldn't have as wide a selection of packages, or wouldn't keep 100% of its packages constantly up-to-date, or some combination of the two.