I got a new mobile last weekend and it is great! The best mobile phone I have ever owned, it is the SonyEricsson K700i complete with a colour screen, mp3 ringtones, and a camera (which I will probably hardly use). mp3 ringtones are cool as it is so much better to hear decent music when the phone rings, Polyphonic tones are great too, but mp3 is even better.
I changed mobile network as well, to O2, mainly because the phones O2 sell are not network customised, and messed up, and also because the tariff is cool - £35 a month gets me 250 cross network minutes, 50 texts, £2.99 worth of international traveller service and free voicemail. Previously my mobile network was T-Mobile, and while they were very good, I decided not to stay with them, as that would have meant signing up for a 18 month contract rather than a 12 month one, and would have got a network customised phone.
I believe networks should not be able to mess up a phone as it is unfair to the user, after all who wants their network logo plastered on the front, somtimes the side and back of the phone? I don't , mind you this is not as bad as messing up the software - on my new phone, if I had gone to Vodafone, and got a Vodafone customised K700i, I would not have been able to use mp3 ringtones, as they do not allow you to use them, unless you get them from their Vodafone Live service, I believe this is because they are covering their back copyright wise. I think if a feature is on a phone you should be able to use it unrestricted, and the network operator should not be able to restrict it. If a network operator wants to customise the phone, then they should onle be able to put an operator logo on the casing, and perhaps in the menu structure a link to their WAP and or other services they offer, and any extra software needed to activate line 2, but nothing else, and not restrict some of the features.
Another bug bear of mine, is locked mobile phones, as there is no need, if you are on contract, after all you have signed up for a 12/18 month contract with the operator, which you can't get out of without paying your way out. I feel it's fair to lock a pay as you go phone, that way it has to be used on the network you bought it on, until you unlock it.