Each to their own. I am somewhat more obsessive about not losing photos than some people. My aim is to never lose a photo while travelling. Apart from card failure prior to transfer I never have. I have managed to "lose" 2 out of the 3 copies of all the photos I had with me on one trip and still lose no images. [Almost all camera cards and 2 x portable hard drives vanished without know cause somewhere between or in Shanghai and Brunei. Still had netbook copy. Loss of the main portable HDD copy is usually "impossible" as I carry it in a zipped pocket (see below) but on this one occasion I was beyond beyond tired and had stupidly left it in a bag.
I have traveled extensively on business in recent years. A camera (or several) is a constant companion. I usually carry an SLR plus a small pocketable video+stills camera (Sanyo XACTI). The following relates to use of the camera as a professional recording tool as part of my job (electrical engineer) plus far higher volume of everything I come across while away.
I carry multiple camera cards and swap them occasionally during the day to avoid total loss due to card failure. SD cards can be read by netbook directly. For CF cards I carry a CF-only to USB cable-less reader on my person as this is most reliable and stupidity proof.
I carry a "netbook" with me almost at all times (even when "tourist wandering".) If I stop for a break I may upload a card or cards on the spot. Occasionally in my backpack while wandering, but not so often. I have a (DOS level) program which incrementally copies new files while leaving the old on card and reports files uncopied, files on card, free space on card. Very simple application based on DOS batch files and XXCOPY [!].
At end of day I copy down any cards to netbook that are not yet copied.
I carry a 500 GB 2.5" USB powered hard drive. This is usually in a belt bag or maybe in my backpack. When flying I zip it into a pocket in my clothes. (Cargo pants leg front pocket works well if you are not socially traumatised by such garb).(Theory is that if I can run smoldering from the burning aeroplane my photos will survive -and if I can't then I won't care).
I copy all files incrementally from netbook to portable HDD. ( XXCOPY /bb /s /h ... sufficeth). If paranoia and disk room allow I may make multiple HDD copies occasionally (on same HDD). On occasion HDD may be updated from netbook during day.
I try very very hard to not delete camera card files until I have a netbook + portable HDD copy made so I have at least 2 copies available.
Typical photo rate while wandering is 500-1000 per day typical with 1000+ on some days. (Multiple shot sequences can add up). Depending on camera and mode hat can add up. RAW+JPG on APSC can be say 20 MB (more on some) so say 20 GB a day. If 500 GB portable drive holds just this data and one copy that's ~= 50days.
As I said, "somewhat obsessive. "
Works for me.
Note: If free internet is available limited rate upload is possible but usually slow. Skype gets through if anything does. Their file transfer rate is slow but they manage connectivity better than almost anything else.