what are you talking about?
facebook plugin was developed by 3rd party, some guy here (don't know his nickname).
also he now works on people's projects for some fee, doesn't probably update facebook plugin, so you're on your own.
I actually do support all my old plugins free of any charge. However due to the Facebook API changing every month it became unfeasible to offer a plugin for a 1 time fee. Some people have used my support many times which means the $20 they paid has translated into less than a dollar an hour for the time I put into the work. Not complaining at all, just explaining why I had to switch to a different model of payment. Now I'm happy to join any team and work on any part of their project including Facebook for a fee. Like you would charge I'm sure for being part of a business team.
But I must say to construct 2 creators credit, they do a phenomenal job of adding things as often as they can. Remember there are a million conceivable items you can add to construct 2. We can't expect them to add all of those all at once. For example I've been on teams where I've added PayPal processing, top score databases, photo manipulation, and of course Facebook features(which change every 30 days). Other options could include facial recognition, gif support, enhanced audio, enhanced pattern matching, nodjs support in terms of MySQL databases(that might already be feasible actually), the list is endless and that doesn't even cover the mobile export options.
So don't think of it as a dying project. Think of it as a work in project, you all got in on the ground floor of html5 which puts you ahead of the curve. Now we just need to slowly add the tools to make us unstoppable as developers.