Microsoft's set a date, laid out their prices and started taking orders, but cheapskates: don't fret! You've still got until the 20th to get a near-finished version of the OS for free. Which you should, for all kinds of reasons.
The obvious ones: Microsoft is still using this to test for bugs, so you using a late-stage Release Candidate now equals faster security and usability updates after Windows 7 later. But more importantly, you get to try Windows 7 for an extended period now — you'll have until March before Microsoft started forcefully shutting your computer down every two hours — before you commit to buying. Thursday may be your last day to nab an official download, but even then, Microsoft says they'll be handing out licence keys for a while; you'll just have to supply your own copy of Windows. Microsoft is practically asking telling you to torrent Windows.
You should try it now, but wait to buy — prices will almost certainly come down before or after launch — maybe not very soon, but certainly before your RC expires and/or becomes an aggressive annoyance.
A few things to chew on while Windows 7's works through its pre-release "awkward phase:"
• A characteristically confusing upgrade chart, which won't help you at all.
• A much less confusing guide to Windows 7's price tiers, as well as a glimpse at some expired deals that you can expect to see again in a few months.
• A full review of the final, soon-to-be-released version of Windows 7, in case you're still not convinced that a free copy of the best version of Windows, ever, is worth downloading.
• Everything else you need to know to enjoy your borrowed copy of the OS for the next six months or so.