If you pre-order Windows 7 (upgrade only) from Microsoft or one of their retailers between tomorrow (June 26th) and July 11th, you can save 50% off the regular price.
$49 for Home Premium, $99 for Professional (US)
$65 in Canada (of course) for Home Premium, $125 for Professional
I'm considering pre-ordering Home Premium to save, the upgrade pricing for Canada for Windows 7 Home Premium is $130 so that's $65 off.
Is Windows 7 reliable though? I don't know much about it - I haven't tried the beta versions. I know my laptop can run it (currently on Vista Home Premium) but I don't know if being an early adopter is a good thing after my incidents with buying this laptop right after the release of Vista and the load of bugs I had to deal with.