Medialets today released the results of JavaScript ^[1] benchmark tests performed using the SunSpider test suite on the iPhone 3G ^[2] and 3GS, the T-Mobile G1 running Android, and the Palm Pre running webOS. The use of the SunSpider suite for benchmarking studies enables cross-platform comparisons among the devices, as they all utilize WebKit-based Web browsers. In the Medialets study, the iPhone 3GS ^[3] outperformed the Palm Pre by a factor of three and the T-Mobile G1 by over a factor of five.

Notably, Medialets also tested the iPhone 3G running both iPhone OS ^[4] 2.2.1 and OS 3.0, revealing that iPhone OS 3.0 provides a nearly three-fold improvement in performance over OS 2.2.1 running on the same hardware ^[5]. The shift to the iPhone 3GS increases performance a further three-fold.

via macrumors