Hi all, I know you guys see a lot of these threads but I need some advice on some specifics.

I need a new camera for my trip to Europe. My gf has the Canon SD800 that we intend to bring along as well. I need a camera that will take good landscape and generally higher quality photos. This camera must not be too incredibly bulky to carry around. I do not want to carry a million lenses if I don't have to as well.

I am thinking along the lines of:
Canon G7
Canon S3

This is mainly due to price and size. Any recommendations? Any must have accessories other than travel charger/extra batteries/extra memory cards (planning on bringing at least 4 GB + laptop). I plan on buying from Costco in case I don't like the camera and I can return it later. I heard the S4 might be coming out in May so Costco is a great option as well. Either way, I just want the flexible return policy (90 days), I'm not buying from Costco with the intent of returning it later, if I like the camera, I will keep it.

Should I spring for a more expensive camera?

Thanks in advance!