Big list of Mac games and the status of their ability to play on Intel Macs, and the status of Universal Binary updates. The Sims 2 has been updated (1.0 Rev D), and the update is free. Myst V needs a patch to install, though it's only the installer that is patched, and the game itself still runs "playably slow" with Apple's Rosetta emulation layer. Older games, like Warcraft III and realMyst, do not have updates, but are reported to run well without an update in emulation. The list is also tracking updates that have be announced but not yet been released, such as Civilization III and IV.
Myst IV, not mentioned on the list, seems to have mixed reports of success. In my case, it installs fine, but crashes during start-up, and this tip does not seem to resolve the issue in my case (nor does the official patch to 1.01, an old patch that has nothing to do with Intel Macs). Another report talks about installation problems but no blocking issues running, so I can't say for sure what the problem is. Thankfully for Myst fans, Cyan always includes both the Windows and Mac versions on the same discs, so we can use Apple Bootcamp to install Windows XP on a partition on an Intel Mac, then install the Windows version of Myst IV. (Blizzard has also included Windows and Mac versions on the same discs for most older titles, in case WarCraft III doesn't run to your taste in Rosetta.)
Incidentally, Sims 2, with the patch, runs much better on my MacBook than it did on my PowerBook G4 (1.25GHz, 1GB RAM). This was to be expected, since the software update allows it to run natively and on faster hardware, but it's nice to see some obvious validation of the hardware upgrade.