no

I'd say definitely. Once you use OSX, you'll never want to go back to anything else.

Apple prides itself on having intuitive, attractive, and easy to use interfaces, and that's exactly what OSX does well. You won't have to mess around with the "guts" of the system to change its configurations, install or remove programs, or anything of the sort. In short, it's a breeze and a pleasure to use.

This is, by the way, coming from someone who used Windows for 10+ years before buying my Macbook last summer, so I think I'm qualified enough to say that OSX blows Windows anything out of the water. I can't speak for Ubuntu, but every version of Linux I've ever tried has been the exact opposite of OSX - unintuitive, headache-inducing, and just plain godawful.

I would get a mac, windows is just amazingly shit!

Just had Windows Explorer 'encounter an error' on me 3 times in a row for no reason so i'm a bit bitter at the moment... Can't MS do anything right?

I'm having trouble believing Mac would have anything that Ubuntu wouldn't have.
But, if you're going to get a laptop, i don't see why not Mac (besides the price), and Ubuntu may actually be easier to install to Mac (although i'm not so sure about it), since the hardware may not be as varied as it is in Windows based laptops from various manufacturers.

Check out iLife. If there are programs there that interest you, buy one. Go to an Apple store and play with OSX, see if it interests you.

If you don't plan on gaming, Macbooks are very versatile laptops. You can run OSX, Windows, Linux, and even boot into a *nix Terminal through OSX.

 Well, since its not for use as your main pc, I'd go for a second hand unit if you just want to try mac.

If you want to try something new from an IT point of view, give a BSD a try:

http://en.wikipedia.org/wiki/Bsd

http://www.freebsd.org/

FreeBSD is the most widely used BSD

http://netbsd.org/

NetBSD has a version that will work on pretty much any computer like device you can think of.

http://openbsd.org/

OpenBSD an ultra-secure OS

http://www.dragonflybsd.org/index.shtml

DragonflyBSD the ease of Ubuntu with all the benefits of BSD.

All these run either Gnome or KDE, so if its a purely aesthetic change you want, ignore this post. If you want a challenge, try one of them.

The biggest reasons to sidegrade (yes, in my opinion is is only a sidegrade) from Ubuntu to OSX are the following:

You're finally sick and tired of editing xorg.conf
No matter what anyone says, as a user of both: rsync is nowhere near as nice as Time Machine.
Quicksilver > Katapault > gnome-launch-bar
Spotlight ~= beagle
Aqua metacity.

Really, what it comes down to is if you want a *nix platform with almost none of the issues that tend to plague linux, you're almost certainly going to love OS X. The *nixiness plus the user interface is really the reason I use it... it gives me access to all the functionality I expect through the terminal, but when I don't necessarily want to need to open a terminal and type "ifconfig | grep ath0 -", I don't have to use it (note: This is only an example, and as it turns out I tend to use that particular phrase a lot on both OS X and linux ).

But I will say to you what I say to everyone who is considering a Mac:
They can run everything that you want to run on computer (Windows, Linux).
They are competitively priced ***WITH OTHER LAPTOPS OF SIMILAR HARDWARE QUALITY***.

No, you won't find a $500 mac laptop. However, look at what you get with the MacBook, and then try and find a similar computer PC-only... you're probably only paying an extra $50-100, if that. For me, the fact that I can bring my laptop to any Apple store out there if there is a problem and get it fixed that day (unless its something large or rare) is worth the premium. Not to mention that you also get access to a copy of OS X in case you like it.

Apple has stayed out of the low-budget PC range on purpose; you end up taking such low margins that you need to overcharge on your high-priced computers to stay profitable. Apple doesn't really have a low-budget range; the mini is their lowest-margin computer, and even that is a healthy profit. So at the higher end, they take lower margins (i.e., can use better hardware and cut fewer corners) because they do not need to counter their low-margin lines. That's not to say you aren't paying a premium -- because you are -- but it does tend to be 'worth it'

If you have any questions to a Linux/windows user turned OSX/linux user (windows now only exists for gaming), feel free to PM me. I can recommend lots of good programs that will do what you are used to from Ubuntu (like an apt-get replacement )

I've thought of BSD as slightly faster than Linux but harder to set up and with fewer programs. There aren't any major architectural differences since both are Unix clones, are there? What are the benefits?

Good point...

Still, it's worth finding out about these things. Whenever there's a discussion on PC vs. Mac, I'm sort of left out despite being into technology. 

No.