It seems to me that as soon as the powers that be start highlighting certain plugins over others, there are going to be serious concerns about bias. Popularity is a user driven metric. "Featured" and "Recommended" are not really user driven. They're driven by the preferences of a small few - either in the sense that plugins are chosen directly, or in the sense that those who write any algorithm decide which factors should be included and weighted.

If they do roll out a recommended plugins page, I think it would be critical that the algorithm be absolutely transparent. Everyone should know clearly why certain plugins are being recommended over others. And, of course, as soon as they do that, there's likely to be controversy and debate what factors are included and how they're weighted.

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Honestly, I'd rather see them deploy a "filter" interface that allows users to filter plugins based on certain criteria like downloads, ratings, forum resolved rate.

For example, if I could select any social sharing plugins with at least X downloads, X out of 5.0 on ratings, and a forum resolved rate of at least X%, then I'd be looking at plugins that are popular, well rated, and well supported.

You could come up with a lot of other useful filtering criteria like that. And that approach seems much more valuable to me than some black box spitting out a list of plugin without knowing why.