I used Dancer two years back for an API, and it performed admirably. I also met the current maintainer at last year's YAPC::NA, and told him I loved the platform.

Really, selecting a tool is a weird business, but what works for me is some combination of the following factors:

• Is it documented? (And to me, that means, can you install the module and, using just the documentation, more or less get the examples working?)
• Is it fairly recent? (This doesn't always mean anything -- Template::Toolkit is my favourite templating system, was was last updated over a year ago, but I can assure you that it's a fine package. On the other hand, if it's fairly recent, but has only been updated once, it may not yet be seasoned enough for prime time. Again, there are exceptions -- Miyagawa writes awesome code.)
• Is there a user community? (For me, this means is there an IRC channel -- mailing lists work too, but I prefer the immediacy of IRC. Personal preference.)
• Have you heard of any of the people attached to the project? (Catalyst is used by mst and his gang, which suggests both that it's supported, and going to be around for a while.)
• Are there any questions about it on Perlmonks?

And I may well try out Dancer2 -- while Dancer was wonderful, now that I'm getting back into a period of study and reflection, I should do that with the latest tools.