Would I be breaking HN etiquette by pubbing it in this thread? Would be easy to find out by looking at my submissions (most from my website) and following my linkedin from there.
I don't think that IPO exits are necessarily harder because barriers of entry are coming down. I think two things:
1. It's a hard economy in general, which is suppressing IPOs overall.
2. The IPOs that the tech community are "used" to were during artificially high periods, setting the watermark at levels that realistically, not many companies can touch.
Addressing your point about copycatting, I think that there will always be competition abroad and it will be successful, but not nearly as successful as the original idea. There are countless Groupon clones out there, but only 1 has earned a $1.2b valuation. Further, I think that an integral part of the nebulous equation that makes a successful startup is the founder/team. Getting the right people behind the right idea is absolutely crucial, and if you don't have the right people, it will almost always fail.
I think that Super Angels are offering startups a metaphorical stepping stone where previously, financing was tough. As the niche grows, however, I think that the stepping stone will start looking more like its own plateau.
I think the fundamental shift that has occurred and carved out this space for Super Angels is that the cost of starting a company has come way down. It no longer takes $1mm to get a startup off the ground (2 guys and a pallet of ramen seems to be standard now). This increased capital efficiency has allowed startups to raise less money to reach the same inflection points that they historically have. As a result, a seed round of $500k can take a company to the point that normally, a $2mm Series A would have required.
Not needing millions of dollars in capital means that startups don't have to knock on the doors of VC firms with large funds. Instead, they can approach a Super Angel to lead a $500k round with $300k with $200k left for 4 to 6 value added investors.
I doubt that even if IPOs rebound, Super Angels will fade away. I think it's more of a tectonic shift and Series A's are de facto turning into earlier, smaller seed rounds.
Highly doubtful, but interesting thought. Talking to the guys at Diapers.com, they want their customers to be happy the first time around. On the off chance they're not, they want them to be absolutely delighted the second time. I'm also pretty sure that the extra cost incurred by including the "mistake item" as well as knowing you're discretely increasing demands on customer service might make the customer acquisition cost not worth the lifetime value.
Even though Diapers.com's customers "cycle-out" after their kids grow up, I think the potential lies in the advisory aspect in their word of mouth (i.e. brothers and sisters, friends, co-workers who are expecting kids/have them). People are always having kids or know someone who is.
In regards to purchasing clothing online, there are some startups making inroads in that category--Fits.me, the one that won the European startup competition, Plugg, comes to mind.