If you are an accounting software developer and want to know how QuickBooks captured the accounting software market by competing with Microsoft, here an interesting book on it. I think every developer should read it:
Microsoft created many products like Microsoft Money, Office Accounting and many others to capture some share of the small to medium market of accounting software but failed. The book is a story of marketing strategies and software design to beat the world. Developers, if QuickBooks can beat the Microsoft, you also can!