If you want to be pedantic, no, it's not a bug but in the vast majority of the software world people use the term “bug tracker” to refer to a system which also tracks new work which isn't strictly a defect.
And, since we're being pedantic, when I said “vast majority of the software world”, that includes the OpenBSD project:
“Sending in bug reports
If possible, use the sendbug(1) command to get the bug into our tracking system. Sendbug requires that your system can properly send Internet email. If you cannot use sendbug on a functional OpenBSD machine, please send your bug report to bugs@openbsd.org.
Perhaps what you are sending in is a feature request, not necessarily a bug. New features are accepted, especially with code that implements your suggested new feature.”
The idea is that if everyone else is converging on "tail -F" supporting that as an alias means that people's habits & shell scripts just work without modification. That seems worth adding a single line to a switch statement to me.
And, since we're being pedantic, when I said “vast majority of the software world”, that includes the OpenBSD project:
“Sending in bug reports
If possible, use the sendbug(1) command to get the bug into our tracking system. Sendbug requires that your system can properly send Internet email. If you cannot use sendbug on a functional OpenBSD machine, please send your bug report to bugs@openbsd.org.
Perhaps what you are sending in is a feature request, not necessarily a bug. New features are accepted, especially with code that implements your suggested new feature.”
http://www.openbsd.org/report.html#bugtypes