We'll start out with what you will need for this:
On your PS3:
1. A Jailbroken PS3 or CFW/MFW installed
2. Mount dev_blind
3. Any FTP homebrew (I use OpenPS3FTP)
On your PC:
1. Any FTP Program (I use Filezilla)
3. PS3 Theme Extractor (if you know how to edit/create .gim files this program is not really necessary but we'll get to that later)
Once you have all this we can get started:
1. On your PS3 mount dev_blind and then start whatever FTP homebrew you are using on your Playstation.
2. On your PC open your FTP program and connect to the Playstation and go to the folder /dev_blind/vsh/resource. Now the file we need to download is the second from the bottom in this folder and it is called xmb_plugin_normal.rco. Maybe you want to put it in it's own folder for the whole operation. it's just simpler that way.
3. On your PC open RCOmage and choose the RCO Input (Path to the file we just downloaded)
Then choose the XML Output (give the xml file just any name like "test" or "new" it doesn't matter)
For resources we need the actual path to the RCOmagegui.exe (In my case it looks like this "D:\Media\PS3\RCOmage"
Leave the box "Separate resources types into separate folders" checked
Uncheck the 4 boxes below and hit DUMP!
4. After a couple of seconds you'll get 2 folders (Images and Text) and an XML file. Look into the Images folder and there will be a file called tex_psn.gim. This is the PSN logo from the XMB. It's 64,1 kb in size. Now if you know how to create or edit these .gim files go ahead and do it. I don't so i simply replaced the PSN icon with one from the theme i am currently using.
5. On your PC use the PS3 Theme Extractor to extract any theme you like to get an icon from to replace the regular PSN icon. once you extract the theme you'll be able to see all the icons used in it and there'll always be 2 files named the same. like "icon_chat_1.gim". I you go over it with your mouse pointer, in the small info window that pops up, one file info will say that it is a PNG file and the other will say GIM file. this is the one we want. Just copy it, rename it to tex_psn.gim and replace the file mentioned in 4.
6. Once the file is replaced open RCOmage again and compile the .rco file and upload it to the PS3. When you recompile the .rco with rcomage check ZLIB under header compression.
DONE!!! PSN logo is no more. Tried it a couple of times and works 100% without freezes or anything.