Actually, Bluetooth 3.0 uses IEEE802.11, not Wi-Fi, as the underlying carrier technology. Wi-Fi is a superset of 802.11 features. Wi-Fi brings broad interoperability, higher level functionality and mandated conformance to established standards. BT 3.0 uses 802.11 as an Alternate MAC/PHY (AMP) layer, has a fixed signaling rate of 24Mbps, and does the "networking" using the BT radio and BT protocols, not Wi-Fi. It is not necessary for a 802.11 radio that is set up to run in BT3.0 mode to be compatible with a standard Wi-Fi access point, as BT3.0 is really supposed to be used to allow higher speed data transfer (about 8x) between two BT3.0-enabled devices, like a cameraphone and a notepad. Wi-Fi Direct is direct competition to BT 3.0, but does it more simply with the one radio, technology and protocol rather than two radios and a mix of protocols that are very different and more costly.
As some of you might remember from way back in 2005, originally the high-speed AMP was going to be Ultrawide Band (UWB), but the BTSIG took a bet on the WiMedia Alliance's MB-OFDM quasi-UWB technology and lost when WiMedia folded its tent in early 2009, after probably a dozen manufacturers had failed to get MB-OFDM silicon to work as promoted.
Bluetooth is not gone, in fact BT Classic (the 2.1 stuff) is in the majority of all cellular handsets sold in the world today, and I think each week something like 20 million BT chips are shipped in product, 90++% of that in cellular handsets and headsets. However, the actual usage of BT is pretty low since most people don't really seem to take to headsets, or if they do use a headset, it's often wired since that eliminates the need to charge two batteries. Like I saw somewhere else, BT seems like the IRDA of the 21st Century, ubiquitous yet little used
That having been said, Since 2004 or so I've been using BT headsets (5-6 models now), multiple BT-enabled phones, even a BT-enabled PDA (remember the old Sony Clie), and am generally satisfied by the convenience and performance. Pairing has gotten way better with 2.1, my phone (BB) only forgets about my headset (Jabra) every second week or three, requiring a repairing effort. But I'm an engineer, and have some tolerance for touchy gadgetry... And no, I'm not a member of either the BTSIG or the Wi-Fi Alliance.