And a nice side effect is: you get updated software, including Firefox 2, and all the other packages Fedora developers have worked hard on.
Actually, no it won't. Simply upgrading to the latest released FC (6) will give you firefox 1.5, not 2. You will still need to install it from a third party (such as remi). Fedora 7 should have FF2 (maybe even 3 ??), but this is still in the test phase, not released.
cheers Chris