DnD: Going Essentials. Now What?

I'll warn you upfront: This post contains no new material or free goodies. Heck, I didn't even get a picture for it. This is simply me asking for advice.

I've decided to go Essentials.

From what I've heard and read online (most of which comes from Twitter, I'll admit), Essentials is simply faster - both for character building and playing. On top of that, it sounds like it is easier for older edition elitists to swallow and easier for newbies (the only people I've gotten to play with) to grasp due to reduced options.

The question for me now, as it has been for every D&D player since Advanced Dungeons & Dragons came out, is 'what should I do with my pre-Essentials 4e books?'

I've got the 3 Player's Handbooks, 3 Monster Manuals, DMG 1 and 2, Open Grave, the DM screen, and Adventurer's Vault 2. I know this is a pittance compared to the hardcore players out there. But for a dilettante such as myself, it was a big investment for the 5 or so games I got out of them.

A lot of attention was paid to the fact that damage and stats were altered in MM3, making it more balanced and 'accurate' (if such a term could be applied), than the first two - so maybe I keep it? Or, maybe all three sold together on eBay would make for a more attractive purchase? I don't know.
Maybe they're worth keeping around as reference material? For the art?

What do people who have been role-playing for years do when they decide to upgrade or switch systems?