Just for comparison's sake, I recreated Jeff's example queries on my in-house table that's ~8B rows. COUNT(*) takes 6s and the SELECT with 2 groups, 2 sums, and 2 averages takes 52s. The downside is that the table takes 600GB of disk space compressed which is a major chunk of our cluster. But here's the kicker - I would never query this table for data I needed in under 5 min so my current performance is meaningless.

Given our access patterns for this table, I'm going to investigate using Redshift Spectrum for it. It seems like a huge win for us.