Philosophically, I wonder if lending will ever really make sense without very large entities who are being audited by the government. Banks are all about trust, after all. I know that banks won't steal my money because they have decades of history, boards overseeing activities, etc. And the idea of lending to friends might seem appealing, but I think it's bad for friendships.
You're afraid of OTC members building a reputation, then absconding with funds once the payoff is large enough? Why are you not afraid of government-approved banks, some of which have spent a century building strong reputations, stealing client funds and joking about doing so while in the elevator?
Yes, I think lending 100BTC to some Internet user with no identity details beyond a web of trust is far riskier than depositing money with a bank.
1. US bank deposits are FDIC insured up to $250,000. So if the bank goes under or is robbed by someone from the inside, the government will cover my loss.
2. Even investing in the stock of a public company through a broker is pretty safe, putting aside the performance of the stock itself. My understanding is that most securities fraud occurs in hedge funds that manage your portfolio for you. There will always be people like Bernie Madoff promising unrealistic returns and printing out fake "statements" with a fictitious value while they invest in mysterious instruments that you're unaware of.