Just read through this thread, was it a mistake, I don't know.
I am one of those who sees tremendous opportunities in hacked domain names, I am generally thought to think 'outside the box' by others (sometimes a compliment and sometimes not), I have made money on ccTLD's, so I think I would be a good candidate as a possible investor in any knew ccTLD that comes along.
I looked at .so and have been singularly unimpressed on the risk to reward possibilities, this 'risk' assessment takes into account such things as possible rule changes, likelihood of being associated with 'spam', likelihood of having domains hijacked, etc.. The domains are not particularly expensive, hell for the right domain $1,000 a year I do not think is expensive (please don't flood me with all the rubbish - in fact please nobody send me any emails offering domains - if I want them I let the owners know), it has to do with what I foresee as what a domain can be turned into and the returns achieved.
The question is would I register or buy a .so domain, the answer is 'yes' - but I would only register or buy one without the realistic expectation of making money on it. If I were into Star Trek I might have gone for 'MakeIt.So', if my or my wifes hobby was needlework then I might have registered 'Sew.So', but they would have been registered as 'hobby' sites for blogs, etc.. Now if I had registered the domain 'Sew.so' would I have tried selling it to a small haberdashery shop emphasizing what a great catchy domain name it was, the answer is NO!
My own opinion is that this suffix, .so, is just too much of a risk except as personal novelty value. I will though sincerely wish those that have invested in the suffix all the best and hope for them that this is one that I missed, although I do not think it is so.