yum update...any way to have it download multiple packages at once?

[Kevin Martin]

When using Yum to update a system, is there any way to tell yum to download more than one package at a time?  If, say, there are 
15-20 packages to update, it would be nice if yum could do the download asynchronously instead of synchronously and then, once all 
of the downloads are done, install the packages in the appropriate fashion.  If yum can't do that are there any other updaters for 
Fedora that can?

Thanks.

Kevin Martin