It was exactly the same last year with the release of the HD2 and I imagine it happens all the time with new phones.
Last year they released the HD2 without marketing online or in any of the UK shops, but by lunchtime they had sold out their stocks. It was the same story over at Vodaphone UK.
Remember, you're probably not the only person to have walked into the shop and asked for the HD7 and I can imagine demand will be high for the first few weeks. After that HTC will probably have more units made.
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