We released on GAE and we're also using Amazon SQS. At our peak load, we were getting over 1.5-2k users streaming in during the initial price drop. CPU Time was our biggest drain: we've combined instant messaging with a local and global search option which eats up resources fairly quickly. I was very surprised at GAE server costs given a userbase that is <10k at this point (given the costs I had to put the breaks on growth very quickly).
The VC approach was for seed-stage capital (~100k) - I found a few "programs"/funds targeting early stage companies. Basically, I'm looking for a business angel that could assume a mentorship role and provide some "smart capital" at this point to scale.