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Beginning 1st January 2009
We will increase the monthly maintenance fee from USD$75 to USD$125 per month. This price increase will apply to all owners of Openspaces on January 1st as well as new purchases after that date. There will be no grandfathering of Openspace maintenance pricing.
For anyone owning class 4 Openspaces on January 1st, they will be upgraded to class 5 by end of January, to further improve the experience people have on those regions.
At the same time, we will be increasing the upfront fee for brand new Openspaces from USD$250 to USD$375.
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First a bit of Logic:
When you increase the price of something it is generally for goods/services recieved or the price going up for the proprietor, for the goods/services used to give you the goods/services. This is logical.
What the Lindens have said: (a recap)
We don't like people using open spaces, with a "load"

The illogical Linden conclusion:
LL wants to increase the cost of a good/service they offer because, in essence, they were outsmarted. This goes to say they never thought people would use these open space simulators for what they did not think they should be used for. (I'm trying to keep a straight face after insinuating that LL was stupid in this regard.) I read no information on a more services being offered nor any information on the cost of upkeep for these services raising.
The post conclusion:
This information presented is basically showing that LL is simply raising the price of an open space simulator because they want more money without giving something up in return (increased goods and or services). If it was true that the cost for them went up it would be logical to see a price jump in regular private regions, which they have semi-recently decreased.
Side note:
I am trying to ignore the blah blah blah legal matters that others are posting, but rather trying to get to the heart of the issue. As it seems LL is simply trying to screw people over.