I can confirm this all is true, but due to USB power being the way it is YMMV. I use hubs regularly for host attachment and for standalone charging. The hub in my desktop monitor is intentionally disconnected from the host in order to provide charging, but it doesn't always work.
A main thing is that some devices are really using the USB connector for convenience, but draw way more power than your USB provides with their wall charger. Check your device wall chargers to see if they provide more than 500mA and keep in mind that anything that goes with a charger supplying more than that will charge slower on the hub, if at all. The other thing to check is the hub, and possibly return it. Sometimes they aren't totally honest about the hub being self-powered. I have had good luck with Belkin in the past, but for all I know they have bad models I never purchased. Also check the electical power supply that came with the hub and make sure it is providing enough current. It is best to have at least 500mA per-port, so a 4-port hub should have at least a 2000mA supply. If the supply is undersized you could see issues where it simply can't provide enough juice. I have seen undersized supplies on cheaper hubs, since the part is cheaper than a higher-capacity supply. Really all the pain starts with the decision to combine the power plug with the USB, but that genie is out of the bottle now. Good luck.
