Lets Talk Dating & Dumping

I read an article in The NY Post this morning about Paula Zahn's ex husband, Richard Cohen, who she left after 20 years of marriage to marry a billionaire. Anyway, Richard has been dating people he finds on a website and has been accused by former Miss USA Julie Hayek (above)and interior designer Nanjoo Joung of being a dater and dumper. My question is how does one become a dater and dumper. He went out with Joung for a couple of months and dumped her for Julie Hayek who he dated for almost two months too before he left her. I guess my question is whether it is wrong to date someone for two months and then dump them? If you date someone for two months are you supposed to be with them forever? Is that some magic cutoff point? Are you supposed to figure out you don't like someone after a few dates? What do you consider dating and dumping? I would understand if these were one night sexual stands and he never returned their calls after, but two months of dating seems like someone, whether male or female trying to see if things will work.