Can call it apple tax, trend tax, or just premium product tax, but the fact is the IPhone is a premium phone, and its a very good one thanks mainly too the vast number of Appz you can get for it.
Its got a good screen size, very intuative as my 3 year old can use it with zero issues, and appz install in seconds and with little bother.
All apple products are about making a statement, and they are all about useability, functionality and ease of use...
You can get it on 3 networks from the shops (to my mind), 02, Orange and Tesco...
You can get the 3G and 3GS, the later been the new one.
PAYG is around £350, contract varies, but its around £180 for a £35 p/m contract. Think 02 does a PAYG one where you topup £15 and get a fair fews mins and texts, and untld internet is standard on the iphone...
5800 vs Iphone would leave the iphone a clear winner, the screens bigger and more sensative/easier to use, the navigation is easier, installing appz is easier, and loads more.
Most phones are very similar these days, your paying for looks, operating system, screen size in the main...
Most new ones seem to have GPS, and most have all video, photo and email functionality...
Iphone is basic as far as standard features, but the appz are what makes it a winner it each and every time for me...