SharePoint 2010 is indeed a great document management system and it will suit your above needs.
Here is an excellent ECM team blog post on what is new with SharePoint 2010 Document Management.
If you are looking for multiple people editing the same document, then you need to have
Office 2010 as Co-Authoring is supported only in Office 2010.
Regards,
Chakkaradeep || SharePoint Solutions Specialist - MCTS SharePoint Dev, WSS Dev
http://www.intergen.co.nz || Twitter: http://twitter.com/chakkaradeep || http://www.chakkaradeep.com