What do you mean by that? Personally I hate ads and wouldn't add them in my games, but looking at the IAP plugin, if this plugin would be working on web, and not just mobile, I would already be very happy. Or am I missing something?
The official plugin still doesn't support subscriptions. It's lacking some other features, which are present in Chadori's Billing addon - product verification, receipts, promocodes etc. And yeah, both plugins are for mobile only.
I don't know if it's feasible to support all those AD networks. But none of the publishers we were working with used Admob for ad mediation.
I totally agree that Scirra should collaborate with big addon creators like Chadori or Mikal - perhaps give their addons an "official" or "recommended" status, provide support and ensure compatibility.