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I started with Blogger many years ago. It worked well for a while and then it didn't. I forget why but I wrote a tool to migrate from Blogger to BlogEngine.net.
BlogEngine.net was good for a while, but I never loved the commenting system. I switched to Disqus and I wrote a tool for that as well.
I've been using the Facebook Comments Box on this blog since I parted ways with Disqus. One issue with the Facebook system is that you won't get SEO credit for comments displayed in an iframe. They have an API to retrieve comments but the documentation is pretty light and so here are three critical tips to get it working.
The first thing to know is that comments can be nested. Once you've got a list of comments to enumerate through you need to check each comment to see if it has it's own list of comments and so on. This is pretty easy to handle.
Last but not least you want to include the comments in a way that can be indexed by search engines but not visible to regular site visitors. I've found that including the SEO list in the tag does the trick, i.e.
I've included the source code for an ASP.NET user control below - this is the code I'm using on the blog. You can see an example of the output on any page with Facebook comments. The code uses Json.net.
I've restored all the comments that vanished after I removed Disqus last weekend. This is after a considerable effort to get everything out of BlogML and into WXR a couple of years ago. At some point I'll just have to give up and decide it's faster to write my own blogging and commenting system but for now Facebook Comments are enabled for all posts.
I just discovered that Disqus started running adverts on my blog without permission. It's probably been going on for a little while and I should have paid more attention, sorry.
By 'without permission' I mean that I'm sure I clicked though and didn't read a terms of service document that said they could do what the fuck they like to my site. And reading other accounts of this issue I'm sure I filed without reading the email they sent out that mentioned this new 'feature' in passing. So in a legal sense they probably had all the permission they needed. In a moral sense they're switch-and-bait scum of the highest order.
They should have made this feature opt-in and then sent out an email explaining it in detail. Some sites don't want to run ads. You could have non-commercial Creative Commons content on a site that is suddenly a commercial concern.
It's a free service and at some point they need to make money, fine. If this had been presented as an option I might have considered it. If they wanted to charge for the service I'd probably have paid for it.
Instead I've disabled Disqus and hastily hacked in Facebook Comments which should be coming online as I write this post.
A side effect of this is that all the existing comments are currently unavailable. I have an archive and will try to get them resurrected soon.
(Since writing this post I have also ditched Facebook comments and now have a fully home grown solution that I moderate by hand.)