I was messing around a little with figuring out some of the keyboard shortcuts in Wave. Here is what I have so far:

While editing:

• Shift + Enter: Shortcut for “Done”
• Control + Enter: Add comment
• Control + b: Bold
• Control + i: Italics
• Control + u: Underline
• Control + g: Poor mans CSS editor (JavaScript text input)
• Control + a: Beginning of line
• Control + e: End of line
• Control + k: Hyperlink
• Control + 1/2/3/4: Convert to h1 / h2 / h3 / h4
• Control + 5: Bullets
• Control + 6: Drops all formatting

While viewing:

• Control + r: Reply
• Enter: Same as Control + r
• Control + e: Edit
• Shift + Enter: Start replying at the end
• Control + Space: Mark all as read

I’ll update this post if I find any more…