Having a card within the slot makes for a much easier “on the go experience, even when compared against a USB that flips upright. They are also getting smaller, my USB 720 is HUGE compared to my SPRINT Compass. Coupled with the fact that the COMPASS, like other USBs of late, is a GPS Module (Verizon still cripples there GPS features in their Broadband devices) and Micro SD card reader, that makes for a nice feature set and justifies the size. That in the fact that, as James notes, I also have several UMPCs, the USB port is then my only option.

With so many PC cards at killer prices on Ebay (I have gotten several Rev A cards for less then $30) it is cost efficient to grab an extra and have the best of both worlds. (It also eliminates the contract extensions) In fact I paid $45 shipped for my new in the box SPRINT Compass. I highly recommend the Compass for the Sprint Users, small, comes with nice carry bag and a very well thought out 6-8 inch USB Extension cable made out of a Rigid Wire that can be bent and stays in the shape you bend it. Makes the USB snap off or bend issue a little less prevalent, although still far from a perfect solution. But with an extension cable you can take the USB Dongle and velcro it to the back or side of the device and make it a bit more out of the way.

But when it sticks out four or five inches from the lappie it’s never going to be pick-uppable, as Luscious points out. The point of the card is to keep it in the device, which largely eliminates any physical robustness concerns.

If some company every develops a small USB modem — i.e. way smaller than the 720 or 727 — I’d check it out. I’ll stick with “grab your laptop and run”-friendly tech for now.

Card slots on the other hand I find much more durable. You can pick up and take the unit with you and still keep any cards securely plugged in, making it one less unit to carry (and lose) and doesn’t require any USB support. Card devices also have a dedicated connection to the PCI bus unlike USB which is shared through a host controller/hub.

It’s one of the great reasons I like the HP mininote so much. I can keep an express card broadband card plugged in the card slot, keep a 32GB SD card inserted in the SD card slot for removable storage, and still be able to pick the unit up and take it with me without unplugging gear or weighing me down with extras. Plus I can use both while still keeping my USB ports free for hard drives and optical drives.

Then there’s the option of using that same express card slot to add new ports like eSata and firewire 800, and now your humble little netbook suddenly becomes a LOT more capable.

Serious users all know this too well, but card slots DO make life cool. They not only make wireless broadband access a “plug in and forget” experience, but the vast connectivity options will bring out the most from your laptop/netbook investment.