Update 2: 1UP Vice President Simon Cox has contacted Joystiq to let us know there are some bugs associated with the current roll out of the conversion formula. Specifically, Cox said the full range of grades (including those marked with a dash in the chart) should have been used in the conversion, and will be when the bug is fixed by the end of the week We'll update the chart and this post when that happens.

Update: Since there appears to be some confusion in the comments, a dash in the "Number" column on the chart means that there's no number score that corresponds to that letter grade.

As part of a planned reorganization, 1UP today switched from its well-known 0-10 review scale to a school-style letter grading scheme. The changeover included a conversion of all existing review scores on the site from numbers to letters, but, as Editorial Director Dan Hsu told N'gai Croal, the site will not be publishing a simple conversion scale to figure out which old number ratings apply to which new letter grades, Hsu says they're keeping the scale close to their chest "because we want our readers to go with our new scoring system and not be constantly translating the new letters back to our old scores."

Where's the fun in that? We compared some old numerical ratings to the new letter grades for ourselves and created the handy (if a bit ugly) conversion chart on the right. Read on for way too much analysis of the score conversion and what it means for evaluating 1UP review scores going forward.

First off, it should be noted that this grade conversion table seems to be consistent across the site. Every review that had a specific number ranking will have the exact same letter grade in the new system -- the grade switch didn't lead to any historical-revisionist tweaking or anything.

That said, the grade conversions themselves might be a bit surprising to those who are used to getting similar marks in school. In most classes a 5/10 on a quiz would be a class-failing F -- at 1UP it converts to a C. There's nothing wrong with this system per se -- in fact, it lines up well with the philosophy that a 5/10 review should correspond to an average (or C-level) game. With review score inflation pushing the industry's "average" reviews into the 7/10 range, though, changing a 5/10 to a C might feel a bit like grading on a curve to some readers.

The lettering system removes some of the granularity associated with the 10-point, 21-step scale -- half point differences are congealed in many cases into identical letter grades (9.5 and 9.0 both convert to "A," for instance). Other half point drops can cause wide chasms in letter grades, though -- the difference between an 8 and a 7.5 in the old system seems smaller somehow than the difference between a B+ and a B- in the new one. Oddly enough, the same half point drop from 6 to 5.5 causes a more incremental letter grade change from a C+ to a plain old C.

Many common letter grades -- such as A- and B -- go entirely unused in the straight conversions, though they do appear in the averaging of editor and user reviews that appears prominently on the 1UP game pages. It's unclear whether or not the full grade range will be used in future reviews.

In the end, it probably makes sense to take Hsu's advice and consider the letter grades on their own merits, without being weighed down by the numbering system of the past. In time, readers will probably forget that 1UP used number grades at all. For now, though, let the pointless squabbling over arbitrary scoring methods begin!