Snape/Harry's face in DD's Pensieve

[lizvega2]

No: HPFGUIDX 89249

I was reading Goblet of Fire last night, and I came to the part 
where Harry goes to DD's office after the divination-dream-scar 
hurts/ episode. When Dumbledore is explaining how the pensieve 
works, Harry notices as he pulls out some thoughts and places them 
in the pensieve. I don't have my book in front of me, sorry, but 
either Harry's face turns into Snapes, or Snape's into Harry. 

I'm sure it's been discussed, anyone have thoughts on what this 
might mean?  

"lizvega2"