ISO range does not tell everything.
Check reviews on
www.dprevire.com,
www.photozone,de or other sites on ISO performance.
I have a 40d which performs excellently at 1600 and 3200, but the 60d might perform 1 stop better.
Another impotant thing: Do not use the full resolution because then you see more grain and lens errors unless you have heavy and expensive L lenses.