Hussar
Legend
Of course hit points have been abstract for decades, that's well known from back in 1e days.
But for me, there's still a big difference between using healing spells/potions in previous editions the equivalent in 4e. As of the materials in 4e that I have, the ability to receive healing is mainly driven by internal resources that are hard to increase. Keoghtum's Ointment may give you an additional healing surge, but a potion uses one of the inherent ones you've got rather than represent healing in its own package. By contrast, previous edition healing is via external resources. That changes how characters can plan to manage their own resources. And it's a change I don't really appreciate. It makes it hard for PCs to pool their resources to support the character whose bad luck is really getting him pulverized.
For the OP, if you like the changes, by all means play 4e. If the changes rub you the wrong way, then don't.
Just to add to Nem D's point. If you look at just about every single class, at any given level, someone is granting hit points without using a surge. Whether it's bonuses to surges, hit points gained on a hit, temporary hit points, whatever, the idea that surges are some sort of hard ceiling on the adventuring day is not supported by the actual mechanics.
This was a bugaboo that IIRC Jason Alexander on the Alexandrian blog has tried to bring up as a criticism of 4e. It just doesn't work. There are WAY too many ways to increase the party's healing for this hard ceiling to be anything more than a very, very soft cushiony one.