I will be finishing a module tomorrow that integrates Magento with Quickbooks Online Edition.
It is not a full sync—only a push—and designed for those shops doing nearly everything with Magento.
The following functionality will be available:
1) Sales Receipts
2) Customer push (from magento to QBOE) --- Customer additions / changes get pushed to QBOE
3) Products push (from magento to QBOE )-------- Product additions / changes get pushed to QBOE
4) Credit Memos
6) Configurable accounts via Magento
I need help testing!!! Please contact me if you are interested in this module. Note that this is for Quickbooks ONLINE and not the desktop edition (that will come later)
View my Quickbooks Merchant Services thread here (module is complete): http://www.magentocommerce.com/boards/viewthread/18650/