Happy to tell you that Microsoft has recently revamped the VSTO online learning center. The site provides information and knowledge about VSTO and how to use it to develop Excel, Word and Outlook solutions and also how to deploy the solutions. From my point of view it’s welcoming as I know that many developers are interested in VSTO but lack the basic information and knowledge about VSTO. Considerably, there are very less resources on VSTO on the Internet too. Hope this helps the programmers who are enthusiastic to work with VSTO.
The startpage is available at Office Development with Visual Studio.
The Excel section can be accessed directly via Outlook Solutions with Visual Studio
Perhaps these pages can make VSTO more understandable (and also get a better reputation) in the Excel Development Community? After all, knowledge is the key to all new areas.