Get an after market HSF for your CPU, such as Cooler Master Hyper 212+ $26.99
Also since you are going for the i5 2500, might as well get the overclockable i5 2500k, for a small investment. ~$10
Make sure your memory has 1.5V or less for voltage, if it doesn't choose one from Corsair/Gskill/Kingston/Mushkin that does.
It is very difficult to say if it has enough juice. It's not known yet what ultra settings in BF3 need, but i'm sure this will be a good start.
And besides you can always get a 2nd GTX570 for SLI if it's not good enough. Generally though GTX570 should produce excellent results at 1920x1080.