No central place for it yet - the beta discussion forum is restricted to iPhone beta-testers only. But John just posted a review at:
http://www.sinosplice.com/life/archives/2009/10/22/the-pleco-iphone-app-beta
and beta-testers are certainly free to post feedback here or elsewhere if they like
http://www.sinosplice.com/life/archives/2009/10/22/the-pleco-iphone-app-beta
and beta-testers are certainly free to post feedback here or elsewhere if they like