At the moment, there's three front-runners for the fourth-generation wireless broadband crown: 3GPP LTE (Long Term Evolution), mobile WiMax and 3GPP2 UMB (Ultra Mobile Broadband). All three standards will offer low latency and theoretical max speeds that will eventually make current U.S. EVDO and HSDPA speeds (and even some home landline connections) seem anemic.

Sprint, of course, is hitching their wagon to Mobile WiMax under the Xohm name. AT&T has said they're planning on migrating toward LTE. Verizon Wireless wants to use the same standard as GSM/HSPA partner Vodafone, and they collectively may choose LTE. Business Week notes that Verizon's decision will have a huge impact on vendors.At the moment, the magazine suggests that UMB is playing a distant third fiddle to LTE and Mobile WiMax. Groups like Parks Associates, meanwhile, don't technically think WiMax belongs in the "4G" category:Parks notes that while Mobile WiMax does have an advantage because it will be first to market, the initial speeds offered by the technology are really only going to be marginally better than existing services. LTE and UMB, meanwhile, will theoretically be able to offer 100Mbps/50Mbps and 280Mbps/60Mbps, respectively, but won't be seen in the wild for some time.