We’re not surprised that there have been some glitches in the Mac App Store distribution of 1 million copies of Lion in one day, but it’s worth paying attention when you download, since some people — undoubtedly a very small proportion — are seeing multiple charges for Lion. Most of the problems appear to be related to using PayPal to pay for the transaction. Some people are having no trouble getting refunds; others are getting the runaround. There’s nothing special to do; just stay alert after placing your order to make sure that if multiple charges do happen, you’ve documented everything for customer service at Apple, PayPal, and your bank.follow link
Mac OS X Services in Snow Leopard
Mac OS X Services let one application supply its powers to another; for example, a Grab service helps TextEdit paste a screenshot into a document. Most users either don't know that Services exist, because they're in an obscure hierarchical menu (ApplicationName > Services), or they mostly don't use them because there are so many of them.
Snow Leopard makes it easier for the uninitiated to utilize this feature; only services appropriate to the current context appear. And in addition to the hierarchical menu, services are discoverable as custom contextual menu items - Control-click in a TextEdit document to access the Grab service, for instance.
In addition, the revamped Keyboard preference pane lets you manage services for the first time ever. You can enable and disable them, and even change their keyboard shortcuts.
Beware Multiple Mac App Store Charges for Lion
Check out the Take Control ebooks that expand on the topic in this article: