I hate to raise old threads, but I've got a problem with usb hubs on my macbook pro (could be an issue with my machine only, in which case I'll have to get it checked out). I've used the 4 port version (also powered) of that d-link hub, and it was complete trash. I dunno if it was broken to begin with, but it wouldn't detect 1 out of 4 peripherals plugged in, and it would randomly disconnect one of my external hard drives. It would also randomly disconnect ports when I plugged or disconnected a peripheral.
I had similar issue with one of those powered white belkin 7 port hubs - the thing would randomly disconnect and then reconnect all peripherals.
Now I know my usb port on that I'm connecting everything to on the laptop is okay because every peripheral connected individually works just fine. It's just when I throw in a powered hub connected to 2 external harddrives, an iphone, and a flashdrive, that problems start appearing.
Meh, any advice? I'm gonna pick up the 7port dlink hub that Kaido recommended today and give it a whirl in the mean time.