Everything Everywhere and BT Wholesale are trialing the UK's first LTE 4G broadband connection from September through to December of this year, concentrating on a specific area in Cornwall. LTE, stands for Long Term Evolution, and is considered the next step in mobile internet access.
At present we have GPRS, Edge, 3G and both types of HSPA. These are displayed as no letter for GPRS, E for Edge, 3 or G for 3G, and H for HSDPA and HSUPA (one is faster download, other is faster upload, depending on location, mostly both in good signal areas)
No letter - GPRS is up to 56k modem speeds
E - Edge is usually between 56k up to 400k (typically if signal is good enough for that strong a edge signal, you get bumped up to 3G or HSPA)
G - 3G is up to 1.8mb and very signal strength dependant
H - HSPA (HSDPA and HSUPA - D for Download, U for Upload) represents up to 7.2mb on modern phones or USB dongles.
Now that that is in perspective, LTE 4G looks to offer up to 40mb connections through a cell network, so no need for a phone line or anything. Phones in the US are already pushing this technology on a select few handsets, with even fewer areas offering coverage, but it is happening.
Remember, this technology is only being trialed now, however phone manufactures often try to keep ahead of the curve to pre-prepare for technology. So if you are buying a new mobile phone after 2011, you need to check if it will be LTE compatible, as I imagine 2012 and 2013 we will all be using it as a matter of course, if our phones are capable.