Which one is better battery type in mobile - Li-Po or Li-ion

Recently, Samsung has introduced a new battery type in the mobile, which is Li-Po.....before this all companies are using Li-ion type.....and the main difference between those - type of material they have.....Li-ion, having a liquid type while Li-Po having a solid material.....both have different characteristics.....but one and major of them is Solid material battery type does not easily produce heat as compare to liquid type of material....... So what do you think guys, which one is more better?