Please see my explanation to the other comment. Thanks.
Edit below in response to your edits.
In the US, options can be written from the day of an IPO and in the case of the Facebook IPO would likely be from existing retail (employees) and institutional investors looking to make revenue on the shares they own by loaning them out for options trading. Though not from the IPO's underwriters who can not loan out shares for options until 30 days after trading begins.
For the valuation I was writing about the up and downside risk of investing at those valuations. It might be obvious to you, but not to others. Actually a lower valuation in some cases could deter investors who had initially heard it would be much higher and they may not understand why an initial prospective valuation decreased.
There are a range of trading strategies that can be used for an IPO. The example I gave was to cover both increases and decreases in the initial trading price that would (usually) allow the investor to capture a (mostly) risk-free profit.
Edit below in response to your edits.
In the US, options can be written from the day of an IPO and in the case of the Facebook IPO would likely be from existing retail (employees) and institutional investors looking to make revenue on the shares they own by loaning them out for options trading. Though not from the IPO's underwriters who can not loan out shares for options until 30 days after trading begins.
For the valuation I was writing about the up and downside risk of investing at those valuations. It might be obvious to you, but not to others. Actually a lower valuation in some cases could deter investors who had initially heard it would be much higher and they may not understand why an initial prospective valuation decreased.
There are a range of trading strategies that can be used for an IPO. The example I gave was to cover both increases and decreases in the initial trading price that would (usually) allow the investor to capture a (mostly) risk-free profit.