Interesting idea using the hearts as anchors to climb on the wall - that's a really nice concept.
The implementation did let it down a bit though... it was hard and fiddly to place the hearts and even though I managed to put them together to form a climbable wall, it wasn't big enough to get to the next level (without teleporting that is...). Also, once the heart was placed, I couldn't see a way of taking it back off the wall to replace it in a different location... so I was stuck with what I had. It also seemed that I could only place hearts within a certain section of the wall, which didn't seem big enough for what I wanted to do.
I think with less fiddly controls, where the game helps you out more, then this game would be even better. Still, good solid entry and I liked the look of it too...