ROM Manager (Premium) (not the free version) lists this amongst its features:
- Incremental update zips (save your data plan!)
- Premium ROMs
- Receive notifications for when your ROM is updated!
- Automatic backups
- Install Queue
- Web Connect
- Backup Download Server lets you easily transfer backups as flashable zips to your computer.
(emphasis mine). I have not tested it myself, but I assume this does not apply to "OTA updates" for your (rooted) stock-ROM – but only for ROMs installed with ROM Manager itself (i.e. where ROM Manager knows the sources of "where to look for").
Second, there's also ROM Installer:
- Many ROMs and ZIPs to download for hundreds of devices
- One click install of the latest TWRP, ClockworkMod and ClockworkMod Touch Recovery
- Backup and restore your current ROM (nandroid)
- Extract apps and data and manage current nandroid backups
- Install ZIPs with the easy to use ROM Installer. Install many ZIPs at one time.
- Get notifications and OTA updates for ROMs and recoveries
- Navigate ROMs and files on the popular ROM hosting website, goo.im
Again, I didn't verify for what ROMs the notifications are valid here. It's very likely the same rules apply here.