Yes, it seems to be ignoring the displaytime over HTTP (the notification is displayed for about 5 seconds, not 50 seconds), but the displaytime is being respected over RPC (my test last night was over RPC).
Texture Cache Maintenance Utility: Preload your texture cache for optimal UI performance. Remotely manage media libraries. Purge unused artwork to free up space. Find missing media. Configurable QA check to highlight metadata issues. Aid in diagnosis of library and cache related problems.