Will Facebook launch a paid membership option?

Today I saw a sponsored poll at Facebook. The question was this:

Would you pay $3.99 a month to have no ads on Facebook?

Is this a way for Facebook to see if they can start charging for a new kind of membership? Like a professional one, where you pay to get rid of all the ads? I took the poll and the results was so far 94% no and only 5% yes (1% missing?). Even though only 5% want to pay for a professional membership at Facebook, Facebook might want to try it. There are probably many reasons to why they want to charge for a new kind of ad free membership, but I have at least thought of two important reasons:

• Regular members won't notice anything different
• Only a few percent members will be a lot of money

I am a free member at Facebook and I always will be, but even though they start charging money for a new kind of membership, I won't notice anything different to my account. Everything will be just the same as it is today. Facebook will not be risking anything by charging for this new membership. Only a few percent of Facebook users will pay, but what if only 100.000 members will pay? They have more than 50 million members as of November 2007 and if only 100.000 members will pay, Facebook will be earning $399.000 a month, and that's from only 100.000 members. I guess that Facebook can be earning more than $1 million a month just by giving their members the option of not viewing ads. What if 5% of their members will pay for this membership, wow... that would be a lot of money! The question is; will Facebook earn more money by charging members for this new account or by giving advertisers the opportunity to advertise to them?