Formerly, hatchlings that were frozen before growing wings could still mature to the second hatchling stage if they had a high enough view count. This is no longer the case, and any hatchlings frozen after the update that led to this will stay in whatever stage they were frozen in. Freezing is limited to twelve dragons every two weeks to prevent hoarding.
On the "Actions" page, freezing is specified only as an action that will "Permanently prevent the hatchling from maturing into an adult", leaving substantial confusion as to what exactly takes place with regard to the hatchling. Similarly vague is the text given when the Freeze action is taken, which says, "You cast a spell on the hatchling that stops any aging." Because of this, each user has a specific idea as to what freezing entails and how it affects the hatchling.
The amount of available 'freezing' depends on your trophy: gold - 16, silver - 14, bronze - 12 and no trophy - 10 freezing actions available.
Some users are against freezing because they believe it to be immoral, similiar to killing and stuffing an animal, and therefore interpret the Freeze spell as something that either kills the hatchling or locks it in suspended animation, so it can no longer go about its life. Other users see it as giving their hatchlings eternal youth, and allowing them to continue living, just never reaching maturity. However, some don't care either way, preferring not to consider the hatchling as anything more than a picture.
There has been some debate about the possibility of freezing eggs, although TJ09 has been trying to work out a way of doing this without abuse and with respect to individuals who feel freezing an egg is synonymous with killing a dragon. One suggested method is to collect egg shards and form them back together to make an egg after a dragon hatches. Another is the creation of infertile eggs, either as a possibility during normal breeding or as a "gender specific action" for all adult female dragons.