Texted me hi

Me Too....dont know who this is

Received a text message on 1/19/13.  Just said "Hi. :) "

I received a text message that said "hi". I didn't reply as I got one yesterday from a different number that was a SPAM yahoo chat request.

Just got a text saying "Heyy :P" from this number. I responded with, "Who is this?", and they asked for me to add them to a Yahoo chat. Obviously a scam.
My mother also received a text from a number she didn't recognize yesterday. What's up with the sudden spam texts? I never get them.