The weekly review is a pretty core part of on OmniFocus. It helps keep you on track and moving toward your goals. It's also a great time to clear out tasks and projects that you just aren't going to do.
The longer I use OmniFocus, the more I break my lists up into separate projects. That's great for organization, but terrible for reviews. At last count, I had over 50 active projects. That is an awful lot to review each and every Friday.
There is a fix, though. It lies in using the review interval setting in OmniFocus for OS X. Simply select the project that you want to change and CMD+SHFT+I to bring up the inspector. Toward the bottom of the pane, you'll see a setting that says "Review every:". Here's where you can set how often to review this project. Let me give you a few examples:
Long term projects
Set the review period for long term projects to a much slower interval. Depending on how long term, it could be monthly, quarterly, or even yearly.
Recurring projects
I have quite a few monthly repeating projects for my job. For the most part, I look these over once a month to make sure everything is in order.
Sort term projects
I stick with a weekly review on all short term projects.
Someday / Maybe
For my someday / maybe list, I simply review every quarter. These items aren't pressing, or they wouldn't be on this list.
That's the gist of how I handle my reviews. I know some people, like David Sparks for instance, have taken to doing a daily review. I don't have the patience or discipline to review my projects daily, even in bite-size chunks.