A force restart/reboot is never a good thing. Only use it when there are no other solution. Just like any pc or mac, when you did not properly restart/reboot, some system files might get corrupted. The same scenario applies to iPhone as its like a computer. Any system need to properly shut itself down to maintain the system stability.

Remember, only use force restart/reboot when you REALLY have no choice.

Wait for FW2.1 and installer 4 if your not fimiliar with cydia. Those important stuff can be saved if you know what to backup.