Tinypng offers a Photoshop plugin for png and jpg image formats.
TinyPNG Photoshop Image Compression Plugin
Looks like $50 bucks gets you a copy of the plugin.
TinyPNG also provides a robust web API to compress images on the fly. Their pricing is pretty reasonable as well. 500 images compressions per month for FREE!
Once I get a chance, I will do some trial runs and see if the compression is up to Google standards.