Following on from the $100 a day post further down the board I have to agree that these type of ads give us a huge boost - especially when they seem realistic amounts.
Someone mentioned $1-$20 a day is harder than $20 plus a day and I am hoping this is right. I have worked very hard to get my 4 sites up to $20 and while I won't keep my foot off the gas I know the hard work has only just begun.
The jump from $5 - $20 a day for me happended within two months and it was largely based on the tips here about ad placement.
My sites have been live between 2 to 14 months and the older one is making an ok amount from affiliate links (average £100 a week).
I don't really have a great deal of advice but as with anything worthwhile do not give up.
The most exciting thing for me is the freedom and positive impact on my life this is having...
For example in November I will go full time for 3 - 4 months on my sites to really push things. I will be leaving the winter and expense of the UK to settle somewhere in SE Asia for a few months.
I will take with me a laptop and the belief that when I get back to the UK next spring I can earn more money this way than contracting for big companies.
That in itself is all the motivation I need.