In another recent post on this topic, I shared instructions for sharing to Buzz and QR Codes straight from Reader's excellent Send to feature. Now, using the new Wave This code, here is how you set up Wave sharing in Reader.
From the main Google Reader page, click Settings in the top right, then Reader settings. Click the Send to tab. At the very bottom, click Create a custom link. In the boxes that appear, enter the following:
Name: Wave
URL: https://wave.google.com/wave/wavethis?u=${url}&t=${title}
Icon URL: http://goo.gl/NpIx
That's it! You can now send links from Reader straight to Wave and immediately start discussions with your friends.