Here is a list of my Top 10 QBO releases in 2018 (in random order):
1. The Custom Summary report
2. Import subaccounts
3. Bills and Applied Payments & Invoice and Received Payments report
4. Quick access to Audit Trail
5. Add an account when creating new items
6. Fixed column headers
7. Progress Invoicing
8. Enhancements to Banking functionalities
9. New access point for importing CSV bank transactions
10. Match split paychecks from Payroll