Can someone explain why 2.8 and 2.71 are so different

Its just I updated as a lot of people I guess, only to get some Rss download thing not sure really what..but

I notice there is a 2.71 downgrader.

But there is also this Tiff exploit that runs on a 2.8....

So my question is, what is so different that the 2.71 downgrader wont work on the 2.8..

I know this has probably been talk about, but trying to search the millions on posts is completely crazy..

If this is a question that has been asked before, I appologise now, I am a bit new to all the homebrew thing, originally thinking it was all about brewing your own beer....

that is a preety good question

We don't get kernal mode or flash access on 2.8 yet... :(

also everytime u upgrade ur psp certain files get bigger than they were(i think it's the vshmain.prx? and a few others), then they don't match up with what they should be and u brick ur psp

It's simple.

Sony don't want you to run anything except their software on the PSP.

So they're always releasing firmware updates. Sometimes they add new features, but the major content of each update is increased security, trying to make it harder to run homebrewed software.

If you like being told what you can do with your PSP, then upgrade every time a new version comes out. If you like having free will, don't upgrade.

im guessing that , as it was released after the kernal mode access was discovered, 2.8 blocked it, but 2.71 still has kernal access as kernal through eloader wasnt discovered until after 2.71 was released
(so in short it was 2.71 update => kernal mode discovered => 2.80 update => libTIFF exploit discovered => 2.81 update)