I've never understood why someone would have more than four tabs open at once.
Since owning the iPad 1, I've never come across a situation where I NEEDED to have four or more tabs open. That's what bookmarks are for. I've had situations where I've needed three, but not four.
I am a Power user and prefer to have lots of tabs open, IMO apple should have put 768mb of ram, it would have cost probs no more than 5 dollars per unit for that little extra ram and could have saved crashes in apps and safari for power users of ipad. Just my 2 cents or pence rather is im from UK!