This is a list of the currently assigned menu-item numbers. If you need a number for an official udeb, don't just grab one, but ask on firstname.lastname@example.org first.
Please do not allocate numbers with too high a granularity. If you have two packages, A and B, and A depends on B, then main-menu will always put A after B. There is no need to assign different numbers to the two; one number will do and will be more flexible, and help avoid BASIC line number disease. In other words, having a bunch of menu items with the same number is a feature, not a bug. Use different menu items only to break ties and do gross positioning in the menu.
For the Squeeze release these numbers were multiplied by 100 from what they were before to give more flexibility.
0 -> 1000 Reserved
1000 -> 3000 Preparation and installer setup
1000 localechooser (!s390) 1100 load-media 1200 kbd-chooser console-setup 1300 iso-scan cdrom-detect 1400 file-preseed 1500 driver-injection-disk-detect 1600 load-iso load-cdrom 1700 ethdetect ppp-udeb s390-netdevice (s390) 1800 netcfg netcfg-static 2100 network-preseed network-console 2110 localechooser (s390) 2300 choose-mirror download-installer 2400 user-setup 2500 lowmem 2600 clock-setup
3000 -> 4000 Disk detection etc.
3500 disk-detect (!s390) 3700 s390-dasd (s390) 3900 rescue-mode
4000 -> 5000 Disk preparation
4200 partman 4400 lvmcfg 4500 mdcfg
6000 -> 8000 Base installation and completion of install
6500 base-installer 7000 apt-setup pkgsel 7300 zipl-installer (s390) flash-kernel-installer (arm*) 7400 grub-installer 7700 nobootloader 7800 finish-install
8000 -> 9000 Reserved
93000 cdebconf-priority 94000 cdrom-checker save-logs 95000 di-utils-shell 96000 eject-udeb 99000 di-utils-exit-installer 99500 di-utils-reboot 99999 dummy menu item for components that should be listed in anna, but not in the main menu