I just installed 10.9 on my 15-inch, Mid 2010 MacBook Pro. gfxCardStatus is now telling me that whenever Textmate (2.0-alpha.9489) is running, the system uses the nVidia discrete graphics card. Textmate is listed in the Dependencies, so it is definitely what is causing the switch. Textmate is also listed as an App Using Significant Energy under the battery status menu.

I don't think this was happening before the upgrade to Mavericks, though it might have come in with the latest build of TM and I just didn't notice.

Anybody else seen this?