It is a drop-in replacement. Deno has a Node compatibility mode [0] which — besides the execution — also applies to LSP, so the Node-specific idioms are processed correctly.

It is not cosmically faster than tsserver, but some — including myself — do prefer it. I wouldn't recommend to change anything if you are busy — but maybe take a glance when in the mood for checking out new things.

[0] https://deno.land/manual@main/node/compatibility_mode