I just went back and looked at the code overhead of using actors over what it might look like with 2.9's parallel collections and the difference would be about

I just went back and looked at the code overhead of using actors over what it might look like with 2.9's parallel collections and the difference would be about 25-30 lines so I don't think that counts as a potentially "large code reduction". Wrapping three bits of code in actors doesn't add much ceremony (which is in fact a great example of how concise Scala can be when adding concurrency!). (And parallel collections came in 2.9, not 2.8 - we'd already migrated, painfully, from 2.7 to 2.8)