Dell showed off its latest notebooks and mini-notebook computers at a press event a couple of nights ago and told me that the mini models, also known as “netbooks,” could be handy for accountants.

Certainly they’re more portable than the standard notebooks, weighing in at less than 3 pounds. There weren’t any big announcements the other night, aside from a deal with Nickelodeon to create a special netbook for kids featuring a “green slime” motif. Still, Dell had some zippy-looking models to show off, and its subsidiary Alienware was showing its latest computers for gaming aficionados. Alienware is also developing a line of peripherals, including keyboards and headphones, to take advantage of its technology and branding.

My main interest at the event was checking out the upcoming version of Windows, Windows 7, which is due out on Oct. 22. Microsoft has promised that the new Windows will ship by that date, and CEO Steve Ballmer even did a public signing a few weeks ago of the “gold” release-to-manufacturing disc. Microsoft is hoping that Windows 7 will help dispel the ghost of the much-maligned Windows Vista, which was widely panned when it was released because of numerous delays, bugs and incompatibilities. Windows 7 has already gotten some favorable reviews from people who have been beta testing the software, including The Wall Street Journal’s Walter Mossberg.

Microsoft has been working hard to stomp out the bugs in Vista, and recently sent Service Pack 2 to Vista computers via its Windows Update service. I only recently got around to using Vista myself. As my old Windows XP laptop seemed to be slowly grinding to a halt, I went out and bought an inexpensive HP laptop from Best Buy, and was pleasantly surprised to find that Vista runs relatively well.

However, I’m afraid that I’ve been starting to succumb to the Windows 7 hype, and I was encouraged to hear that Microsoft and several computer makers plan to offer free upgrades to Windows 7 so as not to disrupt sales of new computers until the October ship date arrives. Once I checked HP’s upgrade site, I discovered that the cutoff date for the free upgrade is for computers bought after June 26. Unfortunately, that left me out by four days, as I had bought the notebook on June 22. Repeated requests to HP’s upgrade e-mail address yielded only a sympathetic note, but no budging on the date.

At the Dell event, I asked a Dell rep about whether they were also offering free upgrades to Windows 7 for people who had recently purchased Vista computers. They said they did, but they too have the same June 26 cutoff date. According to the Dell rep, Microsoft has imposed June 26 as the date for all computer makers to offer the free upgrades.

Why Microsoft would make the date June 26 instead of June 22, which would be exactly four months before October 22, is anybody’s guess. One would think that Microsoft, which makes accounting software too, would be able to count properly.

Maybe it’s just as well to stick with Vista for now anyway, at least until Microsoft comes out with Service Pack 2 for Windows 7.