I'm not a big fan of the joke here, I have to admit.
But if you're going with this design, the lettering doesn't come off as dialog, for a few reasons.
First, there's not dialog balloons, but if you want to avoid them, that's ok.
Secondly, comics traditionally use hand lettering, or something that looks like it. The font you've used (Myriad, Frutiger, or Segoe, I'm guessing?) is very formal, and interferes with it reading as dialog.
Also, by convention people read from left to right, top to bottom. In this design, the "what happened..." should be read before the "I lost..", but because the "I lost" is on top, that will often be read first. I'd suggest moving the "what happened" to the left of the middle of the X, and the "I lost" below the Y. You can also break the sentences on multiple lines to make it fit better.
I don't mind the drybrush shapes of the X and Y, but you should flip the y character around. That is, if he used to be an "x", remove his lower right leg.
that way he looks more like a lower case "y", which always has the lower leg to the left side.
it's getting there. I'm not sure about this, but maybe the y should have a bit of a "stub" where his leg used to be? Very small, so he's still a y, but enough so it's obvious what the X is talking about.
As far as the lettering, it's getting there. If you want to try using a comic book lettering font, try this site:
http://www.blambot.com/fonts.shtml
IN the design section on the left, any font without a red dot next to it is free, and they're pretty good quality.
ISABOA on Jun 25 '08 
