I don't think DPreview even reviewed the Ricoh yet.
As far as the S80 vs S70- I'd probably take the S80. All reviews indicate that it is much faster, especially focusing.
From DPreview:
Where the S70 could feel sluggish, overall impressions of the S80 are much better - it feels very 'snappy' in everyday use, rarely - if ever - keeping you waiting. Focus speed isn't the best in its class, but it isn't far off, and is a lot better than most previous 'S' models. Importantly, it seems noticeably (and measurably) faster than the S70, and it rarely struggles even in low light. Continuous shooting performance is perfectly acceptable for a camera of this class, and there are none of the buffer-related limitations seen on so many competitor models.
Conclusion
So it was a great relief to discover that the S80 (which we presume to use the new Sony 8MP chip) not only offers noticeable improvements in performance and control, but also manages to increase resolution without a significant increase in noise...
The addition of dedicated ISO and AE-compensation buttons on the body make the photographic process a lot more fluid, and the results are superb. Most of the serious issues we had with the S70 - including purple fringing and focus problems - have been eliminated, and the result is a camera that seems perfect for the serious photographer itching for SLR - style control in a compact body.