We used to have 3 variants of on the record: yes, no, and ok to list as part of roundups (but not to describe in detail). The third category was prone to misunderstanding and abuse so we got rid of it.
Now that companies are getting 100k from YC and other incubators (AngelPad) they have a longer runway and more time to get their product right for launch.
my guess is that people don't want to get lost in a sea of startups. Hard to cut through the noise...especially if something big launches the same day(i.e. mint etc)