Gestures on Lion
There are currently some issues with swipe gestures when using Reeder on OS X Lion. To get swipe left/right working, "Swipe between pages" has to be enabled for three (Trackpad) or two fingers (Magic Mouse), see "System Preferences" → "Trackpad" or "Mouse" → "More Gestures". Swipe up/down seems to be broken, the only way to get them working seems to be to hold alt/option while swiping. I'm still looking into this, hoping to be able to address this issue soon.
Reeder is a Google Reader client, which means you need a Google Reader account to use the app. Don't have one? No problem, you can get one here:
When using Reeder, all changes will be synced with Google Reader. This means if (for example) you read an article in Reeder it will also be marked as read in Google Reader. The same is true if you read in Google Reader. When syncing the next time, Reeder will just pick up the changes.
Reeder crashes on launch. Help!
Press and hold the option/alt key when launching Reeder. You can now reset all data and settings using the "Reset Reeder…" button.
Please note: This operation can't be undone!
Reeder does not work with my Google Apps account.
Some users reported that changing the password did the trick. If this does not help, enabling 2-step verification and creating an application specific password should get Reeder working again. Please see this help article (Getting started with 2-step verification) for more information.