Even I noted this change using battery usage app. And it seems to drain more current at night when I am not using it at all, though this is not a coorent statement to make as app activity also probably depends on how active your friends are and how often they "push" status changes etc to you.

I will do a more detailed current drain analysis to may be help TGalal identify areas/situations of high current drain and then he can probably find a way to optimize it.

EDIT: I noted a 30-40mA drain when using Wazapp on 3G. I will now try to compare this with only Google Talk logged in, as even Gtalk is XMPP based like Wazapp.