I am in no way making an argument for/or against either device when I make this point, but I highly recommend getting hands-on with the Bold before dismissing it as too big. While the overall measurements make it out to be 88xx in size, RIM has done a good job making the phone smaller in your hands. All parts of the phone are beveled to avoid the 'brick in your hand' feeling.
Of course the Jav/Curve form factor is small(er), but the Bold is not the giant people make it out to be.
Keep in mind that if you make the decision on which phone to buy because of 3G, then make sure you are picking the right phone for the right network.
T-Mobile is using 1700 MHz where as AT&T and Rogers uses 850 MHz and 1900 MHz for their 3G network.
If you have T-Mobile and you are getting the Bold to use their 3G network then you will be disappointed when you end up only working on the EDGE network instead.