After months (years?) of anticipation for the slew of new gltd's, my prediction is that they will do no better or worse than other gtld's that have come after .com, .net and .org.
I'm talking about .info, .biz, .travel, .coop, .mobi, .tel and also country code extensions that have been marketed as gtld's, like .me and .co. If these handful of extensions haven't made any significant breakthrough, why would anyone expect the news ones to?
I think the above extensions have already served as the litmus test for the new ones that are coming. Each extension will have some hot, related words or terms that really suit it, and these will be used by individuals or upstart companies for cool sounding names. Otherwise, many words and terms won't suit each extension. For example, will babyclothes.xxx or TucsonRealEstate.xxx ever be viable domains someone would use? I think some of the gtld's will also flame out, once registrations do poorly.
I don't think there will be any real take up of a new gtld to rival .com, .net or .org in numbers, but there will be a market for the ones that have commercial appeal and a strong related keyword(s) to the left of the dot.
Years ago Frank Schilling wrote that one possible extension that could get a good take up would be .web. I tend to agree with this because it's a short word that has always been used when talking about the internet, and would also suit mobile sites which are seeing good growth right now. I guess you could make the same argument for .net and ask why it doesn't seem to approach .com in appeal, but I think .web sounds cooler than .net. So if a .web extension is born I may take a look at registering some of those, but I still wouldn't bet the farm.
Back to .ca, I saw one .ca sale in the DNJournal.com sales report this past week, and that was:
Lentils.ca - $2,888 (sold at Sedo)