Everything depends on your niche and the traffic you get from geo target . Like if you wrote one post on Option trading and promoted it in USA traffic networks than the money you can get for one click is much better than other . When you write post first check that how many advertiser are their in that keyword and geo target place they are looking for .
I beg to differ on stuffing the site with good content. Don't give your targetted reader all the information that he needs. If he has read all he needs to read, chances are he'll say thank you and bye bye. If you give just enough information to whet his appetite more in each and every article of yours, chances are he'll click on your advertisements (eg. adsense) to get more information. Stuffing the site with good content is different from targetting the site with relevant keywords. You don't need tonnes of content but good choice of keywords.
It depends on how much effort you decide to commit. If there's full-time involvement, 6 months should be a reasonable target.
depend on which keyword you go for, if you go for competing one then it will take you 1 year and you will make more than 1$ per day after that. If you go micro niche then you can make easily 1$ per day if you hit first page in one day which is possible with good optimization!
You can actually earn $1+ in a day from day one, depends on your niche, i say go for loans, credit cards as they pay high add your 50 articles or so and get the social submission done to sites and WALA your done! earnings will come in!!!!!!
I think you could within a couple months pretty easily, do a load of social bookmarking & articles linking to your site, put some adsense on your site, and a dollar a day won't be hard to make! Hope it helps