According to the Samsung UK Twitter account, the Froyo update for all Galaxy S phones in the UK is on the way, and is set for release on every carrier by the end of September. They’ve given themselves a full two months of wiggle room, so this seems like a date you can put some faith into.
This is still good news for everyone outside of the UK. The update may still be in the development phase, but a September release means carriers in countries outside the UK should be receiving the update in the same timeframe (which is good, because the phone has already launched in several countries.) If you simply can’t wait, you can try out the leaked Froyo ROM that is already available here.