UPDATE - EB Games Australia's Steve Wilson has said the claims are "99 percent bullshit, really".

EB Games Australia and Microsoft haven't always been on the best of terms. Last year's mass recall of 360 consoles by the retail giant, for example, probably didn't go down too well in the boardroom. But have things gotten even worse? They may have, as an alleged source from within EB Games has told Kotaku Australia's Logan the two companies are locked in a standoff over faulty 360 consoles. Seems that between last year's recall and overall RROD failures, EB Games have around AUD$10 million (USD$8,867,000) worth of 360s gathering dust in their warehouses. They accepted the returns themselves, rather than forcing thousands of customers to go through Microsoft's support network, and want MS to reimburse them. Microsoft are, supposedly, having none of it.

The source reckons the tussle has become so dire that EB Games have threatened to drop the Xbox range of products from their stores altogether. Serious business. Especially when you consider they're the nation's #1 gaming retailer. I called countless EB Games stores across the country this morning, and at each store, was told the same thing: they had no Premium 360s in stock, and had not received new stock since before Christmas. None of the managers I spoke to had any idea why they weren't being restocked. Most of them sounded more than a little pissed off about it. Little strange that store managers would be kept in the dark about such serious supply problems, unless...well, unless the supply problem was at a higher level.

Bear in mind these claims are, at this point, unsubstantiated by either EB Games or Microsoft ("Microsoft does not comment on rumour and speculation"), but the consistency of the supply "issues" across the country is, at the least, highly suspicious.
Microsoft Refusing to Take $10 Million Worth of Defective 360s from EB Oz? [Kotaku AU]