It’s difficult to understand why Google didn’t develop an online photo editor: it would’ve integrated with Picasa Web Albums, Google Docs and other Google services. Right now, Picasa Web Albums is just an online extension of Picasa, a popular software that lets you manage your photos. Unlike Picasa Web Albums, most Google services work online and don’t require additional applications.

Instead of migrating Picasa online, Google acquired Picnik, an online photo editor that already integrates…