I had a PR5 given to one of my old sites a few months after it launched, but it took a hit once Google started lowering adult sites' PR =(
maybe this can help you all : http://generalities.opiniaoweb.com/...-many-links-you-need-to-have-a-high-pagerank/
It is possible if you can write high quality knowledgeable posts and get high pr back links according to your niche .
You can get PR7 If you can afford to spend 1000$ a month. Throw money and next update you will have a PR7
he was a beginner.. he couldn't have any money to buy not even a link.. it is surprising how some of us have a great luck to get links from big sites..
As I recall bigweblinks went to PR7 in one update (less than 6 months)... So yes it is very possible...