Is it a chat bubble that's like half filled in? I realized there's two different notification icons for text messages and media messages. I thought my Nexus was telling me I had a failed message but instead I realized someone was sending me a picture.Noticed the same thing today. Sometimes I'll see the message itself, sometimes I'll see "new message". Also the icon in the notification status bar for a new SMS is sometimes different. Sometimes I'll see the standard smiley SMS. Other times I'll see a different icon, like a chat bubble without the smiley inside. No idea what it means.