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As for me If you had a doubt, don't buy it. If your 3GS are still working incredibly and needed no other features from iphone 4, you should maximize its excellence. I suggest you to wait for the new updates.
 
hate to be all non-apple, but why not look into google android?
just look into it, compare it to the iPhone, see which you like better, etc. i mean it wont hurt you.. go to the store and try both out!

i have neither so i am not favoring both... and since im nice, also try out the new Windows Phone 7 (or whatever its called)...

Cheers for all the advise guys, I've decided to wait it out. The 'if you don't know you need it, don't buy it' advise was especially good!

I have had a look at the google android phones, but for me theres still too much wrong with them. Every review picks up on little things which would really bug me with the interface. Give it a year and I will seriously consider the Andriod phones. And I might have a look at the Windows 7 phone.. I've heard it's pretty good!
 
I would wait. If this was still August, I probably would suggest to go for it. iPhone 4GS or whatever is within the next 6 to 7 months. Android phones between February and around June will probably be a good alternative phone.

so now 6-7 months is 'wait, don't buy'? Soon this place will be advising people to wait when a new product has only been out a week.
 
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