Voting is an important part of the democratic process. The electorate makes a decision or expresses an opinion that is accepted for everyone. Some parts could be interested in the election results deviation without anyone else noticing it. However, ensuring that the whole voting process is performed correctly and according to current rules and law is, then, even more important. We present in this work a review of existing verification systems for electronic voting systems, from both academia and the commercial world. To do so, we realize a fair comparison against a set of representative voting verification systems, by using an evaluation framework. We define this framework to be composed of several properties and covering important system areas, ranging from the user interaction to security issues. We then model the natural evolution of verifiability issues on electronic voting systems, which are influenced by restrictions on current laws and by technological advances.