A bit dubious
I'm all for grabbing the new version and taking it for a spin... getting a bit disenchanted with Chrome and went off FF ages ago. IE9 is pretty good but still not as good as Chrome so I'd hope IE10 would be good.
BUT that "protracted development" makes me nervous it might not quite be there yet. Not that I use IE as my main browser just yet anyway so maybe I'll take the plunge as and when it wants to install.