Messages in some views are sorted by the order in which they are received. But messages Snowl receives in the same refresh cycle get inserted into the database in groups by source because Snowl parses the response data synchronously. So, during a major refresh cycle that pulls a lot of messages (like when you restart your browser after leaving it off overnight) those views show messages that are grouped by source, which is confusing, inconsistent with the appearance of those views after a series of minor refresh cycles (like when you leave your browser running during the day), and doesn't look as nice. Snowl already initiates refreshes of multiple feeds simultaneously and asynchronously, it's only the parsing of the response data that is synchronous. Snowl sources should sleep for a few milliseconds after adding each message to the datastore to give other sources time to add messages.
Fixed in changeset 08cb97d510a7.