Firefox has an Addon Debugger.
Also https://addons.mozilla.org (AMO) has much more accountable guidelines than https://chrome.google.com/webstore/ (cws).
cws has a lot of issues with lengthy reviews as well https://groups.google.com/a/chromium.org/forum/#!searchin/ch...
Over at AMO you can monitor the review queue position of your addon, and there is even IRC channels #amo-editors and #amo to talk to.
Review mails have specific feedback about issues they find.
Google extension reviews, bug reports (e.g. Chrome or Android bugs[1]), googlecode site support[2], are an ever growing super massive black hole.
[1] e.g. https://code.google.com/p/android/issues/list?can=2&q=blueto... [2] https://code.google.com/p/support/issues/list