iPhone 3G users in Japan: SoftBank Mobile just unilaterally made your monthly data fee cheaper. Maybe.

The company is revising its monthly JPY5985 all-you-can-eat "Packet Flat-rate Full" data plan, required for all iPhone 3G contracts, to a cost of JPY0.084 per packet. The new minimum fee drops to only JPY1695 for up to 20,175 packets; the fee rises with usage from there, up to a maximum of the old cost of JPY5985 for 71,250 packets or more.

In other words: it's still all-you-can-eat, but light users can now shave some coin from their bill. At the same time, SoftBank Mobile is strengthening its E-mail (i) service for iPhone 3G to store users' mail indefinitely with no scheduled deletion, though a mail data limit of 200MB or 5000 messages will still apply.
http://www.softbankmobile.co.jp/en/news/press/2008/20080805_02/index.html (English)