Mary Jo Foley got a chance to see a note sent to certain testers of Vista SP1 earlier this month and quite a few interesting factoids have turned up in it:

Q: How big is SP1?

A: “Windows Vista SP1 is approximately 45 MB when delivered over Windows Update and is designed to not significantly change the UI or regress application compatibility.�

Q: What are some examples of “support for emerging technologies and standards?�

A: “With SP1, Windows Vista can boot via EFI (Extensible Firmware Interface) on an x64 machine. SP1 supports ExFAT, a new file format that will be used in flash memory storage and consumer devices Support for SD Advanced DMA Support to improve transfer performance and decrease CPU utilization is part of SP1.

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Microsoft, Windows Vista, Vista SP1, SP1, Windows Update, Service Pack 1, FAQ, Vista FAQ