Basicly zip upload is a small dashboard control that allows you to upload a zip file to the media section of umbraco. All files in the zip get created as media items and it also respects folder structure.
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Source code includes improved UI including the ability to require selection of a media folder.
CAUTION: Upgrading to allow Zip Upload to work with 4.5.2 requires you to overwrite the ZIP Archive library (ICSharpCode.SharpZipLib.dll). In some cases this throws and error when trying to create a package via the Developer section. This shouldn't be a problem in production environments, but tread carefully.