Sounds like application developers who are treating the iPad like a notebook or desktop computer. For years, developers have been able to code willy-nilly without having any concern over memory utilization, for the vast majority of applications.
And, yes, I'm sure that the fact that the developers of the apps that are out there now didn't have access to real hardware - or even know how much RAM the iPad would have - during development. They've been developing on the simulator with essentially unlimited RAM. Now that they've presumably gotten hardware, you can expect improvement in updated versions.
The unfortunate thing is, there are way too few developers with experience in the kind of constraints imposed by iPhone/iPad. iPhone apps, I think, benefited perhaps unintentionally by iPhone's small screen with necessarily limited UIs, and the small RAM of the 2G and 3G models. It forced developers into accepting limitations that they somehow think have magically disappeared with iPad.
Here's something to put this into perspective: when I was in college (just after the last dinosaur died off... or in the mid-70's) our campus computer had 8MB of RAM. (It did, however, have the advantage of virtual memory, which iPad doesn't have.) And that's only because we "cornered the market" in Fairchild solid-state RAM for the IBM 360/67. It typically served 100 or so simultaneous users.
iPad has 32 times as much RAM, and more than 500 times the processor speed (>1000 MIPS for iPad vs. .98 x 2 processors for the dual 360/67's we had) . All to support one user, not an entire campus' academic computing needs. And we have apps crashing because the have "run out of memory".
Even considering the demands of a graphical UI, this suggests that the average skill level of programmers has dropped dramatically in the meantime.
