I’ve been asking this whenever I’m around people who might know:
Where you own both… The plural so often makes a better sounding storefront, but the singular keyword often scores 10x or more exact match searches per month. Pointing the singular to the plural with a 301 redirect seems to be the general advice. But that would only generate what little type-in traffic the singular domain got.
In my own experiments I’ve been able to score top 10 in Google for exact match plural keyword search, but disappear off the search results for (much more competition) singular (using 301 redirect approach). Wondering if building out the singular keyword domain could make a difference. But also, don’t want to risk duplicate content penalties.
Probably the best answer I’ve received so far comes from a well known domain developer (whose name I won’t mention because it was in an email and I haven’t asked his permission to quote him) . Would still hope to get a definitive answer with some examples and stats at some point.
Long story short: I personally would develop the variants and have one site be the “money site” and the other sites be doorway or reference sites that link to the money site.
301 redirect makes sense if there is existing traffic but odds are not much so you are better off creating something that is capable of being indexed and ranked.
If you run across any good info please let me know in the comments.