We are experiencing problems with Tailored Audiences again. They are being marked as “Too Small” although there is no reason to believe they are small (they are in the thousands of valid, recent users).
Today, when uploading the audiences using the web interface, the “Uploading data file…” dialog window freezes at “Uploading… (99.0%)” and stays in that state forever (cross checked in different browsers and operating systems, and with different user accounts).
Problems with Tailored Audiences started two weeks ago, but @jillblaz confirmed last week that they had been sorted out.