The introduction of this special indexer will facilitate a smoother transition for subgraph users and allow decentralized indexers ample time to catch up on indexing and bolster their infrastructure.
We don’t see it as so special but we also didn’t want to spin it up without letting you all know. 
Any additional transparency from E&N regarding current subgraph traffic and migration plans would help indexers prepare more effectively. While this information has been closely guarded in the past for valid reasons, we may be nearing a pivotal moment in subgraph migration where sharing a bit more information with the community would be beneficial.
I fully agree. We’ll share future plans for upgrading more folks to the network as well as the chains and subgraphs included in the upgrade Indexer with plenty of lead time.
When it comes to subgraphs on the hosted service, our thinking is to share a live list (or table) of those that are public—with meta information like chain name/ID, entity count, database size, query volume—to help Indexers decide which of them they want to pick up.