In OS X 10.5 ("Leopard"), tail can now follow multiple files! Look:
bash-3.2# tail -f *
==> DirectoryService.error.log <==
2007-11-06 12:30:52 EST - T[0xB0103000] - Attempt #1 to initialize plug-in PasswordServer failed.
Will retry initialization at most 100 times every 1 second.
==> DirectoryService.server.log <==
2007-11-06 12:40:19 EST - T[0xB0289000] - Registered node /Cache
2007-11-06 12:40:19 EST - T[0xB0289000] - Plug-in Cache state is now active.
2007-11-06 12:40:19 EST - T[0xB0185000] - Plugin "Active Directory", Version "1.6", is set to load lazily.
2007-11-06 12:40:19 EST - T[0xB0185000] - Plugin "PasswordServer", Version "4.0", is set to load lazily.
2007-11-06 12:40:22 EST - T[0xB0081000] - Network transition occurred.
Nice!