I recently had a project where I needed to migrate a 2007 sub-site from WSS 3.0 to SharePoint Server 2010 Enterprise.  I needed to move all of the lists and keep the metadata (Created Date, Created By, etc) in tact.  Here's how I did it...
<ol>
	<li>Move Content DB from MOSS/WSS to SP2010 using the <a href="http://technet.microsoft.com/en-us/library/cc263299.aspx">attach db</a> method and use the <em>-UpdateUserExperience</em> switch</li>
	<li>Export the list using the <em><a href="http://technet.microsoft.com/en-us/library/ee428301.aspx">Export-SPWeb</a></em> Powershell command and the <em>-IncludeUserSecurity</em> switch
<ol>
	<li><em>export-spweb -identity http://www.sp.com/oldsite -ItemUrl Lists/MyList -IncludeUserSecurity -IncludeVersions All -path \serversharefilename.cmp</em></li>
</ol>
</li>
	<li>Import the list into your new site using the <em><a href="http://technet.microsoft.com/en-us/library/ee428322.aspx">Import-SPWeb</a></em> Powershell command
<ol>
	<li><em>import-spweb -identity http://www.sp.com/newsite -IncludeUserSecurity -path \serversharefilename.cmp</em></li>
</ol>
</li>
</ol>
You should now have your list in the new site with all of the permissions and metadata in tact!