Grid Hosting VS Shared Hosting

I have a site that is getting about 60-70K pageviews a day, and recently my hosting isp (godaddy) told me that my site is taking up too many shared resources and that I should switch to Grid Hosting.
I plan to triple or quadriple my sites traffic to approx 200-250K pageviews a day and have everything in place to do this, but before I can do this I must upgrade my hosting.
Go daddy's grid hosting is in the BETA phase, but reports around the internet seem to be positive...
I was wondering if anyone could advice me on what I should do:
Banwidth wise, I am fine,
but should I spring to upgrade to
1. A dedicated server
OR
2. Grid Hosting

Switch to Amazon AWS. Then you won't have scalability problems in the future.

http://aws.amazon.com/

It's also incredibly stable and they constantly improve it. They even reduce the price they charge you every now and again, passing on their costs savings as they become more efficient. There aren't many companies that do that!