The new First Look Client has a new feature that the recent blog post didn't say anything about. That feature is Dynamic Reflection, and that means working Mirrors in SL. I haven't taken a look myself yet, but Gwyneth Llewelyn has made a video and put it on youtube.
This looks pretty cool if you ask me. Now this does not mean this will be in the normal client any time soon. There have been features in Beta before that never ended up in the client, because they didn't work(well) for many people. But this is cool non the less.
In response to Gwyneth's vid, ZATZAi made a longer video showing how the new mirror feature works on different shapes an shiny values. Even Mirror to mirror reflections work.
Not only shiny prims mirror but also ripple water reflects!
Picture by Chandra Page
And i love Chandra's comment on it:
"It's like shiny, but it's shiny on fire, being chased by ninjas and helicopters, and the ninjas are on fire, too."