Both are completely different things. It takes ten years to build a company. You can go jump up and down or left and right but it really takes that long.
Twitter is 3rd generation product built on of hype (Myspace->Facebook->Twitter). The first two generation still have to make enough company to be called interesting. Twitter can become big but is it big enough given the hype? The latest trend seems to be building apps around twitter. Two years back it was building facebook apps.
<blockquote>New Moto: Build something people are willing to pay for</blockquote>
If they are not willing to pay for it, they dont really need it. Be it a virtual gift or freemium or clean ur toilet service. As long as people pay, you have a business.