I agree that it is probably a change in the webkit api. You can see the extent of the changes as terminal performs the swap to the prior edition of Safari. It is certainly much more than simply removing and re-installing a program. I should have said that I am running 10.6.8, and so the only change was to Safari. Since the earlier version had no problems and I simply did a routine upgrade, I would not expect the earlier version of the api to have any problems. This may not be true if the api changed with a system upgrade from 10.7.3 to 10.7.4, and therefore may be involved in more than just Safari.

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