Why is php 5 so rare?

Just a few observances here:A properly setup server will not cause a moment of downtime when apache is upgraded. All that happens when apache is upgraded is that the server itself restarts apache. That's it. nothing fancy, nothing major, that's it. This goes the same for php, the only difference being that php isn't "restarted", it's transitioned over.
This isn't as much the host thing as it is a developer thing. Traditionally, hosts don't upgrade not because they're lazy, but because they don't know how. There's a huge difference there.
Another misconception.
A properly coded site (in php4) will have absolutely no problems migrating to php5. There are no major issues with updating php4 to php5, and, after almost 3 years in existence, there should be no script at all that's php5 incompatable. If there is, that's laziness, but NOT on the server side of things, on the developer's side of things.
Again, a misconception.
PHP4 and PHP5 are practically interchangable. You don't need scripts to be written specifically for php5 to have it WORK in php5.

So, if most php4 and php5 applications ARE interchangable, why aren't more individuals running php5? Because they're afraid:

The "hype" now is that there are major incompatabilities in almost all scripts between php4 and php5. This, frankly, is incorrect.
From a developer's standpoint, I find that php4 and php5 are seamlessly integrated well enough. It's not like php6 where register_globals will be gone altogether (that will be a nightmare and probably lose a LOT of host support), but there were a few things cracked down on over the years.

Starting with php4, the php group did some major code changes, from register_globals (may have been php3, don't know) being turned off to other things. Why? Because they saw php being abused, and poorly coded in. I'm not going to say I agree with this move, specifically, because I do in fact use globals apparently (though I'll be damned if I know how), though every inch of my code is secured.

In php5 more security restrictions were put into place, causing more errors in php4 applications. THIS is why individuals didn't just rush out and update to php5. The same will be with php6 and register_globals. In fact, php5 may be the last WIDELY used version of php, if they keep the register_globals stuff up.

Anyways, I digress, just wanted to contribute my 0.02 as a developer into this.

__________________
Linux Tech Networks, Quality, affordable Linux Systems Administration
SimpleForums - Easy Install SMF Forums
Toll Free: 866-546-8914 (linux-14)
AIM: twhiting9275 ICQ: 153158973 MSN and Email: tech@linux-tech.net

We had a few issues with compatibility, but with some simple tweaking php5 is now enabled.

__________________
o|Intec Networks Hosting Solutions
o| ITHost.ca - 1-877-ITHost-1
o| cPanel Shared // Dedicated Linux // WHM Resellers // Domains
o| 100% Uptime - View

I don't think php 5 is rare at all. It might just be the servers you are looking at. Every single server except 1 offers php v.5 but it might just be a good coincedence.

i think the answer to all that is simple, lots and lots of scripts have been developed in the 4.x.x and the new 5 wont provide flexibility to those scripts...i have heard it makes them slower and sometimes obsolete. so hosts that provide php5 will definitely get less customers
[in my opinion]