Aside from being a higher firmware version number-The only thing added in 5.00 is the PSN network icon in the XMB where you can get direct access to the Playstation Store for themes, videos, game demos, PSX & PSP games(for $$ of course)The demos, themes and wallpapers, etc. are free though.
They do have the popsloader and the 1.50 kernel add-on for 5.00M33 out now, so if you really wanted to have the latest offering of CFW, you could go that route...
I just updated in the last week or so from 3.90M33 myself, and the only reason for that is I was updating my UPT memory stick and needed to make sure it worked OK -The new firmware works as it should. So I guess its more of a personal preference than anything. I don't insist on having the latest and greatest right this instant. I usually wait until the kinks are worked out, or if I run into a game that requires a higher firmware version (which is rare), but not just because its new.
i dont see why people choose to stick with old firmware, i understand its safe that way and there really is no need if its working fine now especially if all you do is download isos and play them fine now then sure but dark alex will normally fix all the bugs within the first week and it doesn't take more then a few weeks for the homebrew that stopped working to get a quick patch; for me its about features and homebrew and everything with 5.00 M33-3 is being made better from custom firmware extender to the new cxmb 3.3 themes and yea it can be a hassle to go through and check what still works and then to check pspupdates.com for whats being updated but personally i wouldn't want to miss the next greatest homebrew or plugin.
