For anyone packaging software on Linux, this now means every major distro - Debian, RHEL/CentOS, Arch and now Ubuntu - supports .service files. No need for bash scripts, custom watchdog and daemonise tools, etc.
Friends don't let friends write shell scripts targeting bash.
For context: Bash is not available|installed everywhere, and has some inter-version weirdness.
Write clean, posix-compliant shell scripts (i.e. target /bin/sh commonly referred to as bourne shell) and you're in a much better position.
On Debian your script will be run by Dash, on OS X it will be run by Bash, on Ubuntu or RedHat it could be different again, but the point is, they are specifically running in POSIX mode, so that you get reliable, reproducible results across systems and even across Bash versions.