Considering buying either the Sony H5 or Canon S3 for an Alaskan vacation a week from now. I know - it's very late (wouldn't mind hearing everyone's opinion between the two).

I want to make sure I purchase the correct memory cards. If you could recommend the correct high speed memory card for me to use the either so that it is the highest quality high speed card to use for full video capabiity as well as excellent still photography.

What is the viewing time per megabite that I should look for? For example, how long of video time does a 2 Gig card allow? Also, what is the largest high speed Gig card I can get for longer video time?

This is for our Alaska trip of 2 and a half weeks, combining small boat cruising and park buses. I was thinking of buying two 2-Gig memory cards (for stills) and one very large card for uninterrupted video - especially due to the fact that on the cruise we are very close to marine mammels and don't want to miss an opportunity to use the best video capability for this purpose. And we also want to make sure we have enough memory cards for still pictures.

Could you recommend any brands to look for and what the cost should be. As far as the 2-Gig cards, we saw the Ultra II high speed Scan Disk 2-Gig cards at Costco for $35, but we are not sure if this card is correct for full video capability and video length, in addition to stills at the highest quality, which we assume this is recommended.

As far as getting a card with an amazing amount of Gig space, we'd love to hear about that as well.