SharePoint Designer 2010 offers a lot of new and enhanced features compared to the 2007 version.
The first thing you will notice after installing and starting SharePoint Designer is the new user interface.
User interface
Now we have the ribbon too... well using the tool is a little bit confusing and not intuitive. At least for me i had some trouble using it the right way and knowing my current position in the SharePoint site structure. I hope this gets better with more experience and usage.
Workflow designer
SharePoint Designer workflows are now reusable... that itself is a great enhancement. Further more you can modify the out-of-the-box workflows like approval, collect feedback or collect signatures. Also new are sub-steps and impersonation steps.
Business Connectivity Services
Integrating external data wasn’t easy in 2007 saying it with some nice words and it didn’t fulfill the expectations. Now we have external content types and we can read and write.
Visual Studio 2010
SharePoint Designer and Visual Studio 2010 go hand in hand and complement each other. Workflows created with SharePoint Designer can be reused in Visual Studio and activities created in Visual Studio can be used with the designer.
So an advanced user knowing business requirements can model a workflow for the developer.
Visio
Visio 2010 can be used too by an user knowing business requirements to develop a process model. This can be imported using the designer to create a workflow for SharePoint 2010.
Custom actions
In SharePoint 2007 it was possible to enhance the out-of-the-box menus with custom actions. Now you can use SharePoint Designer 2010 to extend the ribbon.
Restriction
Yes, restriction is the thing that was missing in SharePoint 2007. Now an administrator can decide how an user can modify the look and feel of a SharePoint site at the server-, web application- or site collection level.
Summary
SharePoint Designer 2010 has gotten a lot of improvements and additions... right now it feels a little bit unintuitive but we will see. Looks like it has a lot of potential and if yes I hope it can eliminate the bad reputation of 2007 version.
Need more SharePoint Designer resources? Please take a look at SharePoint Designer.