There has been a number of reports of slowness in the version 4 web application. We're investigating and actively working on bringing the performance back in line.
Edit: The speed of the software has been improving over the last 30 minutes. We'll continue to monitor the situation.
Edit: The speed of the system seems to have settled, we're continuing to monitor it though to make sure the issue is fully resolved.
Edit: The speed of the system has been consistent for the last hour. We're therefore closing this incident.