This is really interesting because they have a cool platform. I haven't tried it much because I haven't been doing the kind of work that requires something like it for a while. But, this new free version and an Amazon EC2 AMI really are making me want to give it another spin. Begs the question though, what's the price after you hit $5 million because then, you'll have to pay to keep playing or migrate your application elsewhere. So, I think I'll still look before I leap! It's Java based for the interested.
Geva Perry from Gigaspaces caught this post and provided some additional clarification. So, I wanted to update my post with that information.
"Nothing happens when you reach $5 million in revenues. You can keep using the product for free. The $5 million is only the cut-off for who qualifies in the first place."