Taylor,
Here are the logs for new iOS5 Twitter app log details & lack of oauth_token in header
Here is the new iOS5 Twitter on custom image upload which fails:
[HTTP_USER_AGENT] => Twitter/3.5 CFNetwork/548.0.3 Darwin/11.0.0
[HTTP_X_VERIFY_CREDENTIALS_AUTHORIZATION] => OAuth oauth_timestamp=“1318875025”, oauth_nonce=“FA8E28BA-50DA-4E75-851E-04BECBA6A6DC”, oauth_version=“1.0”, oauth_consumer_key=“IQKbtXXXXXXXX0HUA”, oauth_signature_method=“HMAC-SHA1”, oauth_signature=“JpbqoXXXXXXXXXXA%3D”
[HTTP_X_AUTH_SERVICE_PROVIDER] => https://api.twitter.com/1/account/verify_credentials.json
Here is the iOS5 TweetBot version that works
[HTTP_USER_AGENT] => Tweetbot/17094 CFNetwork/548.0.3 Darwin/11.0.0
[HTTP_X_VERIFY_CREDENTIALS_AUTHORIZATION] => OAuth realm="*", oauth_consumer_key=“8AeXXXXXXXX1QGA”, oauth_nonce=“049DF542-C01C-42F7-B19A-4A6DFF4E64B5”, oauth_signature=“dcEempXXXXXXXX1Yvaws%3D”, oauth_signature_method=“HMAC-SHA1”, oauth_timestamp=“1318875280”, oauth_token=“15412585-JRcq4ssXXXXXXXXXnur6yNvJqlG2”, oauth_version=“1.0”
[HTTP_X_AUTH_SERVICE_PROVIDER] => https://api.twitter.com/1/account/verify_credentials.json