You mean the 'drag window to the edge and it decides to take up the whole display height' type feature? I'm constantly amazed that anyone likes that, and I was most pleased to find out that it can be turned off (Computer -> Properties -> Advanced System Settings).
Windows is not as conducive as OS X to arranging windows in an attractive fashion, mainly because Windows windows have pretty big surrounds and take up more space, and it seems that most people have always just run everything maximised, which perplexes me. The snap features in 7 make it all the harder to arrange things nicely because if you try to arrange windows aligned to the top or the side of the screen they madly expand to maximise or at least take full height - I haven't yet run into a situation in 7 where I wanted that to happen.
The snap feature I would like in OS X is Windows' mouse snap-to default button in dialogs.
On 10.6.4, good to see SMB is on the list to look out for; it has been embarrassingly slow in SL to date, not good if you're trying to show something to a Windows person.
Other than that ... might as well bring up the nested sorting in stacks bug AGAIN, and the iTunes dashboard widget bugs that have now survived 2 major and 22 minor updates to OS X. Long live my pet bugs

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