expand note about rustup

Author: pietroalbini

posts/2022-09-22-Rust-1.64.0.md

@@ -157,10 +157,36 @@ In the future, we hope to provide simpler APIs that require less use of
 low-level details like `Poll` and `Pin`, but in the meantime, these helpers
 make it easier to write such code.
 
-### `rust-analyzer` now available via `rustup`, no longer in preview
+### rust-analyzer is now available via rustup
 
-Users of `rust-analyzer` can now obtain it via `rustup` on the stable and beta
-channels, not just on nightly.
+[rust-analyzer](https://rust-analyzer.github.io/) is now included as part of
+the collection of tools included with Rust. This can make it easier to download
+and access rust-analyzer, and makes it available on more platforms. It is
+available as a [rustup
+component](https://rust-lang.github.io/rustup/concepts/components.html) which
+can be installed with:
+
+```
+rustup component add rust-analyzer
+```
+
+At this time, to run the rustup-installed version, you need to invoke it this
+way:
+
+```
+rustup run rust-analyzer
+```
+
+The next release of rustup will have a built-in proxy so that running the
+executable `rust-analyzer` will launch the appropriate version.
+
+Most users should continue to use the releases provided by the rust-analyzer
+team (available on the [rust-analyzer releases
+page](https://github.com/rust-lang/rust-analyzer/releases)), which are
+published more frequently. Users of the [official VSCode
+extension](https://marketplace.visualstudio.com/items?itemName=rust-lang.rust-analyzer)
+are not affected since it automatically downloads and updates releases in the
+background.
 
 ### Stabilized APIs