This is exactly why I am waiting until 2009 to finalize my navigation electronics purchases. I encountered a middle-aged voyaging couple yesterday (they'd been "out" a number of years, and their boat looks like it) who used an SSB set just for reception, not transmission. When I asked why, they said that paper charts and careful monitoring got them a great deal of weather and local conditions information, and that even in fairly remote places, WiFi was almost always available. They were mulling over getting an Iridium phone, but seemed to find the SSB/mail/Pactor combo unnecessary, because they had both GSM and timecode cellphones, a VHF and an SSB to receive cruiser net info. They said NAVTEX reception was frequently poor in the real world, however.
Sway will appreciate that the only place their tech choices failed them was in Cuba, where WiFi and cell coverage don't appear to exist.
My own inclination is somewhat opposite in that I want full transceiver operation of an SSB for weatherfax and slow data transmit, and might consider a satphone strictly as a backup, because the charges are high, the coverage is spotty in places, and as a "modem", they are very pricey.
Hearing from actual current voyagers that WiFi is becoming ubiquitous was of great interest to me. I don't think it will alter my plans much, but it's certainly an argument in favour of getting or making a directional, boosted WiFi antenna so that you can get Internet connectivity out in the anchoring grounds from a marina on shore.