Even if new cameras are to be announced, they won't ship in time for your trip. That aside, you also need time to learn how to use your new camera.
The Canon XS is good, but you should look at the Pentax K-x. It's a better camera for about the same price.
I'm in the market for an entry level DSLR and I'm wondering if I should go ahead and purchase one or wait a bit. Is there a particular/common time of the year when new camera releases are announced? I'm leaning toward the Canon Rebel XS. I'm no rush to purchase one however I would like to have it by mid-March in time for a trip in April.

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