Originally Posted by
alanw
So...you'll definitely save time and hassle by switching,
This is completely subjective. My wife is your stereotypical "average" PC user; she has an XP laptop for work and her personal laptop has been running Vista for the past few years, and the Windows 7 beta and now RTM for the past few months. She has no problem switching between the 2 laptops and she tells me that she never feels like she's "hassling" with the OS on either.
Originally Posted by
alanw
and have a more aesthetic computing experience to boot.

This is also completely subjective, but let's not forget that moving from XP to Windows 7 will also provide a much more aesthetic computing experience.
Regarding presentations, I've been doing all of mine on PowerPoint 2010 for the past 6 weeks or so and I'm pretty impressed with some of the new graphical / experience improvements.
In my opinion, I feel that you can achieve your stated objectives by picking up a Windows 7 laptop on or after October 22, because:
* Windows 7 has a much more pleasing / user friendly interface than Windows XP
* You'll have *far* more models to choose from to get your desired battery life within your budget
* Compatibility with your peers that you share data with
* Going from XP to Windows 7 is a smoother / quicker learning curve than going from XP to Mac