Portal Dashboard - What's the ideal number of portlets?

What is the ideal no. of portlets to be displayed on the dashboard? I think it should not be more than eight. That's my opinion.

I have seen a few customers making the dashboard heavy with as many as 12 portlets. With all the configurations required to process the synthetic portlets, it becomes a bottleneck for the performance of the site.

Also, the user will be stuffed with too many information on one screen making it least presentable. Chances are there that the user might miss a portlet!

What do you think it should be? Any comments?