The tips above for flashing and recovery are very handy and may help a number of folks get their devices running normally again.
I've observed that the frequency of reports about stock Iconia systems getting stuck in reboot/recovery has been increasing. There seems to be some correlation with the age of the devices. From what I can tell, when this happens to a stock system during typical use, the problem is almost always hardware. This problem has often required motherboard replacement to resolve. I assume the cause is probably NAND failure in most cases, because it is a consumable resource. Depending on usage patterns, it seems that some devices may be more prone to such failure than others.
In cases where this problem has occurred during normal operation to an unmodified device running a stock ROM, I have not heard of anyone recovering from the condition by flashing anything. The exception to this has been when the original problem was actually caused by flashing either an incompatible ROM/boot loader combination, or by a flashing failure that occurred during a custom flash or OTA flash operation, where for example, some units lost battery power while updating, others where booted prematurely, some were flashed with the wrong images, etc.
Keep in mind that if you are running a stock system, there's nothing that is likely to cause a boot loader or other ROM partition data failure other than hardware failure, because on stock systems those partitions are very well protected. If you are not flashing these partitions to deliberately make changes, then the only thing that is likely to affect them is hardware failure.
Bottom line... If you or some previous owner did not break your ROM by flashing or using root privilege to modify protected ROM data -- e.g., /system -- then flashing is not likely to fix it. On the other hand, if you or someone did corrupt any of your partitions in a flash operation or privileged modification, then the tips above for flashing and recovery may help resolve your problem.