I built a seaside app on Squeak last year and ported it to Pharo in October. So far I've liked Seaside a lot better than Rails, and Pharo a lot better than Squeak. Pharo is a nice, clean smalltalk with a professional UI useful for the developer. We've even started selling the app. on a very small scale and have had great feedback on the flexibility we gained by using a Smalltalk, Seaside, and an object database