These gigantic moves in the S&P 500 need instant analysis. They demand thought and action. Here's a look at two joining the index and two that are checking out.

Coming in:

eBay

(EBAY) - Get Report

: I would use the strength to sell this stock. I think that the time to own stocks that sell at 70 times earnings is over, and this will be a convenient exit point.

Electronic Arts

(ERTS)

: Good solid story that's not ridiculously overpriced and has a lot of momentum. I would hold on to it.

Going out:

Alcan

(AL) - Get Report

: Tough call here. The company is doing better than expected. It might make sense to swap out of

Alcoa

(AA) - Get Report

(which I own) and move into Alcan. It's a well-run aluminum maker.

Barrick Gold

(ABX)

: Premier gold producer. I own it, and will buy more of it into any weakness from this subtract.

This is a special look at Jim Cramer's commentary. Click here for a free trial to RealMoney. Once you sign up, you can read the rest of Cramer's column on the S&P here -- as well as access all of our premium content.

James J. Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. At the time of publication, Cramer was long Alcoa and Barrick Gold.

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