Ramadan, do you think it's actually possible for Egyptians to overthrow Mubarak's regime?

No, but the change is imminent and would be a smart move. I say this because military has not intervened and it can. If the regime cracks down with or without military support and without a promise of reform, it will be overthrown. The military only kills so many of their own. These are the same people who have relatives on the street.