Question about skill gems

When a skill gem is ready to level up, is there a way to see what the skill's stats will be when you level it up? It shows what the requirements will be to level the gem, but not what the skill will be able to do after you level it. I want to know what the changes will be before I level the gem, in case the increased mana cost is not worth the additional effects. If there is a way to do this, I couldn't figure it out. Any help is appreciated.

the wiki has such information
http://en.pathofexilewiki.com/wiki/Skills

Ok, thank you. So right now there is no way to see this info in game I take it? Is this going to be implemented soon? Seems like a needed feature.

Its been suggested, and hope to mouse over the + key, instead of mouse over the gem to get those information.