Are you retarded or what?? 

So what you want?  
You think PSP Wiki is have trusted sources? Its copy of Wikipedia and users are adding information not Sony.  
In PSP Wiki is written: The latest reported firmware version shipping pre-installed on new PSPs is 5.50 (confirmed by a few people who buyed a PSP-3000 Special Edition (Harry Potter Version).   
This have trusted sources???: (confirmed by a few people who buyed a PSP-3000 Special Edition (Harry Potter Version)?? OH YES SONY CONFIRMED THAT!!! OR WHAT?? [and even world bought is written wrong]  
Actually a new PSPs have a version 5.70 or higher. Even in Wikipedia is written: [5.70]This firmware is only available pre-installed on new PSP-N1000 (PSPgo) models and cannot be downloaded. SO ARE YOU BLIND OR WHAT???!!! AND HOW CAN BE THIS POSTED IF IT DOESN'T HAVE SOURCE?  
And 5.70 is also installed on new PSPs 3000. I can confirm that. On PSPs came with limited edition GT bundle. I bought one.(already sold it because its not hackable)  
If you still don't belive me read there:  
http://forums.pspslimhacks.com/user-help/3594-psp-3000-firmware-5-70-a.html  
http://forums.mformature.net/showthread.php?t=6088  
  
This is not fear: few millions people read pages in Wikipedia but actually one user who thinks he is god is editing as his ass wants.  
  
SO IF CITATION ""[5.70]This firmware is only available pre-installed on new PSP-N1000 (PSPgo) models and cannot be downloaded.[THIS CAN BE MY SOURCE FOR PSPs GO]"" AND INFORMATION IN LINKS DOESN'T HAVE SOURCE THERE IS ONE POSSIBILITY YOU DON'T KNOW WHAT IS SOURCE AND YOU ARE TOTALLY STUPIDLY RETARDED.  
  
SORRY BUT TRUE.