Gamma-ray bursts (GRB), the most energetic explosions in the universe, were proposed as major cosmic ray accelerators and the most promising astrophysical neutrino sources. Recently, 28 energetic TeV - PeV neutrinos are indeed discovered by IceCube, the cubic-km sized neutrino detector in Antarctica. Although the origins of these have not been confirmed yet, a previous search by IceCube implies that GRBs are very unlikely to be the sole sources of these neutrinos. Is the standard GRB model wrong? Are there other energy bands that have not been probed yet? What can be revealing if we detect a neutrino from GRB or not? The talk will address these questions above, and compare the old and new GRB models through this unique neutrino messenger.