I've done a pilot experiment to test this with English progressive voicing assimilation and got encouraging results: Novel Popout.pdf. I'll be expanding on this pilot study in a few months.
I have been awarded a grant through the NSF's East Asia and Pacific Summer Institute to conduct a similar study on tones in Mandarin Chinese. Listeners will be presented with both novel and normal tone sequences and will be asked to identify specific tones. I will be in Beijing this summer to do this experiment. I plan to have the results of both experiments written up by December 2008.
Jeff Berry 2008-04-29