According to the Microsoft online store, the $499 32GB Surface model (without the Touch Cover) has sold out in a day.

If the Microsoft Surface is on your holiday wish list, you might want to place your order now.

According to the Microsoft online store, the RT tablet's $499 32GB model (without the Touch Cover) sold out in a day. It is now scheduled to ship "within three weeks."

Pre-orders for the the two remaining devices  the $599 32GB and $699 64GB, both with the black Touch Cover  are still expected to deliver by Oct. 26.

Microsoft did not immediately respond to a request for comment about the shipping delays, and provided no further details on its website.

Microsoft for the RT version of the Surface tablet on Tuesday. Touch covers are available separately for $119.99 each in black, white, magenta, cyan, and red.

The pressure is on for Redmond, which will release its Windows 8 operating system on Oct. 26. Several days later, it is hosting a Windows Phone 8 launch event . PCMag will be there for both events, so stay tuned for all the details.

Limited pre-order supplies are common amongst highly anticipated products. Last month, the iPhone 5 in just one hour, topping 2 million orders and pushing delivery dates to two weeks. Many iPhone 5's ended up , though.

Meanwhile, the 16GB version of Google's Android-based Nexus 7 tablet less than a month after its release, leaving only the smaller 8GB available for purchase through the Google Play store. About a week later, the Asus-manufactured tablet was .

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