In a desperate attempt to avoid sliding into irrelevance Google has boosted Wave with the launch of extensions.
Now showing up in the navigation panel, it works much like the Labs feature common across Gmail, Docs and the like and makes a neat depository for developers working with the Wave API.
Obviously enough, these extensions show up as Waves with the content of the wave providing information about the extension and an install button. Most Wave extensions are fairly basic so far with simple games and organisational tools the mainstay, but there aren't many since the 10+ that were rolled out by Google in February and none which really strike me as game changing.
Consequently I'd say Google needs to bite the bullet and integrate Wave into Gmail before it becomes truly irrelevant. There are interesting technologies in Wave such as real time communication, conference style collaboration and the ability to 'Playback' Waves if you join them late, but at the end of the day it is one more unnecessary inbox to check. I hadn't checked mine since mid-January, and I haven't heard anyone discuss it in tech press circles since then.
So Google, see sense before it becomes another knol and realise this simple fact: in its current incarnation no-one has time for it...