Yes, LXDE is a fantastic Environment - I think its the best system, on the grounds that computers should be as efficient as possible and consume as little as they can.
Previously I was using it because I had an old laptop that wasnt a performer. Currently I have a hex-core PC. So I can afford to run the latest KDE. Which is great for showing off, but its not as important as resource consumption. Especially if your using the system all day every day (eg. for work). Don't get me wrong I still love KDE and GNOME, but when I think of all the computing devices in the whole world, collectively consuming excessive power, and contributing to CO2 emmissions - I immediately thank God for LXDE!
And today I just discovered the best LXDE distribution called "lubuntu". The consistency of the quality of themeing/branding is truly awesome! There has been 5 releases of that distro, and all 5 had clean, complete and impressive artwork/themes/branding. Its one thing to consume few resources. But quite exceptional to look good at the same time!
As to lxappearance changing metacity or xfwm4 themes. I think making it work like GNOME2 is also a good idea. One of the most impressive things you could do with GNOME2 is to use gconf-tool to alter the value of every registerd application with commands. "lubuntu" has the gconf-tool installed by default, and I think it must be possible to create a key for a LXDE application setting. However, by default gconf-editor doesnt seem to store any LXDE keys!
Also, just today I became aware of xfconf and xfce4-settings which do a similar job for xfce desktops. Some settings are accessible from LXDE like xsettings, displays, xfce4-keyboard-shortcuts, and finally xfce4-power-manager. But the one I want is xfce4-desktop which contains settings for the Desktop. I tried installing the xfdesktop4 package, and start it up, but got a SESSION_MANAGER error!
Which led me to this forum, where I found this command:
"pcmanfm --set-wallpaper /path/to/your/wallpaper.jpg" and I can confirm it does actually work. If anyone knows how change LXDE settings programmatically, Id like to know if this is possible with gconf-tool or xfconf-query or any other tool.
Finally I think your right about LXDE attracting a bunch of new users with small changes to make it look better. "lubuntu" definately does this. And thanks to openbox there is allot of great "conky" scripts that can make it stand out aswell. What I would like to see with LXDE is a next generation conky widget tool similar to "rainmeter" on windows machines. (examples here:
http://customize.org/rainmeter ) Conky is efficient and if it had more support for animation, LXDE could use it to really compete with KDE and GNOME3.

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