Talking of the DST point, how do you manage this in your apps? Say we're in the UK, you schedule something to run at 9am GMT. In the summer, the timezone changes to BST, so 9am GMT is still 9am UTC. I've never seen a scheduling app where you say 9am UK, and have it automatically switch GMT to BST. The closest I've seen is "use server time" where you have to setup the server to automatically apply the DST rules - but then you have issues when working with out of sync DST rules, such as those of the US.