So, this may sound like a dumb questions but, I'm planning on getting a 16GB IPhone but my Itunes has 3000odd songs on it taking up 18GB. IS there a way that would allow me to only select a few songs onto my IPhone and keep my IPod with the full 3000 songs as I don't want to use so much memory on my Iphone. I know I could get a 32GB but is it really worth it?

Also, when the contract says Free Wi-Fi? Does that mean it's free to surf the web?

Yes you can select what goes on it - no need to shove all your songs etc. on it at once. Free WiFi means use of WiFi hot spots like those at stations and coffee shops etc. Other WiFI networks like yours at home are obviously free and nothing to do with your mobile operator.

Cool Thanks. So when going online with your IPhone, how much is it exactly?

Depends on your tariff and who your mobile operator is. Most offer between 0.5GB and 1GB a month inclusive with your minutes and texts etc. You really need to shop around and see what suits you best. It might also be worth holding off a few weeks until Apple attempt to fix a reception issue that some people are suffering.

Usage is included in the iPhone contract information, ranging from 500MB-unlimited with FUP.
After you go over the usage permitted on the mobile network, you're subject to extra data charges, which can be found on their website.

Have a read of this if you want to see what the different networks offer & what the costs are:

http://www.moneysavingexpert.com/deals/cheap-iphone

I have a similarly sized music library to you. When I first got my 3G 16GB was enough to store all my music. Since then I started to use my phones large screen to watch videos and obviously downloaded a lot of apps. Because of this I have had to take a lot of music off which isn't ideal. For this reason when I get iPhone 4 it will be the 32GB model. Also the HD video recording will be memory hogging and I see myself making good use of this.

Perhaps you should consider this before you choose your model. You don't want to end up wishing you got the bigger capacity after only a few months!

T-Mobile allow you a generous 3GB of data on an iPhone tariff - but still don't charge you if you go over it.

I've had an iPhone for 2 weeks and my total data usage (cellular) is standing at 225MB, and that's with it checking for email every 30 mins.

T-Mobile's website doesn't seem to have any mention of the iPhone on it now, other than "iPhone 4 is coming soon!".

No iPhones in the shop (as the 16GB & 32GB 3GS have been phased out, & they don't have the iPhone 4 or the 8GB 3GS yet), & no mention of iPhone tariffs (as they will presumably be offering new tariffs once they get the iPhone 4)...

The Internet FUP makes no mention of the iPhone. It simply states that plans with internet access have a FUP of 1GB, and plans with internet access on an Android phone have 3GB.

Given the other networks' changes once they started offering the iPhone 4, I wouldn't be surprised if T-Mobile changed its FUP once it had the iPhone 4.

Still, maybe it won't... 3GB would certainly put it above the rest...

OK I've seen on with 500MB Allowence. Is that enough or too small?

It depends on how much you would use!

When I'm at home, my iPhone uses my home WiFi.

When I'm at work, my iPhone uses my work WiFi.

Consequently, my 3G data usage isn't a great deal (never gone over 100MB in one month).

But it depends on where you would use your phone, & what you would use it for.

500 MB will be fine for a typical user, but as others have said it really depends on what you'll be using it for.

People who listen to lots of music over the air (e.g. spotify), or looking at loads of youtube and/or live streaming TV will see their usage jump up quite quickly and so for those users it makes more sense to go for a higher allowance, or an unlimited plan if they can find one.

If you will be mostly listening to your own music on the iPhone itself though, and just browsing the net and/or using apps like facebook to access data then 500MB will likely be plenty for you.