Made a small addon for Warlocks on 3.3.5a that automatically manages Soul Shards.
You set how many you want to keep, and if you loot more it will delete the extras right away.

Includes a simple GUI for setting your shard cap + checking how many you currently have,
and a minimap icon for quick access.

Clean, lightweight and does exactly what it should – nothing more.

Download: https://github.com/andreash-dev/ShardKeeper-WotLK