How I personally enjoy reading..and writing reviews is this...
first get the facts out of the way, say what the game offers in each category and then give your own first hand experience on what you think of it. State your opions and give a rating in each section.
categories that seem to be the most popular...
-Gameplay
-Graphics
-Sound
-Controls
-Storyline
-Multiplayer
-Bonus Materials
-etc.
Now you don't have to get into major detail with every category shown but if you touch on each one in it's own way, you got yourself a killer review that people will enjoy.
Another thing I see people do which is nice to see is a pros and cons listing. This helps the reader understand the balance of the game. If you are not into writing that sort of list at least incorporate the good and bad within the review. If there's a glitch, let readers know. If theres one thing, whether big or small, that you especially enjoyed about the game, let us all know.
A good review is one that lets you know what the games all about and then say how it really is. Also sometimes you have to be fair to other gamers taste in gaming. Say, for example, you hate turn-based games (like myself)... well then it may not be the best idea to review final fantasy and give it a 3/10. If there is part of a game that you may not have enjoyed but you can see where others would like it, state that.
And just remember, every great review is written to grab the readers attention and let him/her feel that they can trust the reviewer and their opinions on the game on topic. <