Let's start with the main players. MYOB and Reckon APS still hold the lion's share of the larger firm market (75 to 500+ users).

Tax and accounting services company CCH has acquired Acclipse and its flagship program iFirm

To answer this depends on another question as there are two answers.

First, its global licensor took back QuickBooks, the household brand name. Then the dream deal with MYOB evaporated.

It raises many interesting questions about the relationship between associations and software companies and how far associations will go in embracing technology