The closed cockpit/cockpit protection debate is interesting and I'm very firmly and vehmently......on the fence about it. So I can only add a few pointers here and there.
Firstly, with respect to F1, and contrary to gut instinct I would trust the FIA on whatever judgement they might make on this on the future. I would very much doubt (or at least hope) they would rush into something because they read some people crying on forums and AMUS+others producing a photoshop. Given their track record (as far as I can recall in recent times) if they decided to make a move on this I assume it would be done in a measured and safe way.
I would take slight issue with the argument that a canopy might fail to open in some dangerous situation like a fire. That doesn't seem to be an argument against closed canopies; rather I'd see that as an argument against canopies that don't work properly. Whilst being a much simpler mechanism, would the same logic not apply to seatbelts; what if the release mechanism fails and the driver can't get out quickly? They don't, so it's not a detraction, and I think the same would apply to canopies if they could be shown to be reliable before being introduced. Also, when it comes to rollovers........I honestly can't remember an example of a driver climbing out of an upside down open-wheel car before Marshall righted it. Am I completely wrong on that?
I totally agree that accidents like Justin Wilson's (urgh......horrible just typing that out

) are freak. But one of the things I appreciate about motorsports is that hasn't usually stopped the pursuit of further safety in my time watching. For example Massa's 2009 accident was certainly freak, but I believe helmets have been further strengthened in response to that, yes? And so motorsport should continue to be in my opinion - finding ways to prevent even the freak accidents, when those ways can be shown to operate safely and as intended.
I don't see open cockpits being of essence to open-wheel racing, but then again I've not been watching for hugely long, and I'm not a driver so this may be just lost on me. Would be appreciated if someone could explain the significance of this from the driver's perspective, for the uneducated!
Final thoughts though, even given all this I kinda hope we don't see some form of canopy/extra protection in F1 or otherwise for many, many years. Unless a lot has been done in private, it seems clear that it's still early days for research in this technology. And motorsport has certainly proved on many occasions that it's hard to rush big changes through, even if it's what some fans or drivers want. If somewhere down the line the FIA or whoever come out and say "we've been researching canopies for a decade now, and with approval of other bodies, industry and drivers this technology is now safe and practical and can be introduced", I'd probably be behind that.