So, I've just upgraded to a new computer (a Lenovo z710). All in all a nice improvement.
This time I went for a bigger (17'') screen -- until now I was using a 15.6'' inches. My old computer is still working well, but it started to become way too noisy/hot for me (it was a Dell Studio 1558 -- and the fan became too dusty -- it's already a 4-years old computer and was never cleaned because to clean it I have to COMPLETELY disassemble it: take the keyboard out, screen, network connections -- really, the fan is THE hardest component to reach in this model).
So, after checking the net (and asking for a recommendation at http://www.reddit.com/r/SuggestALaptop/), I decided to go with the Lenovo z710... almost everything went Ok: it has a large back-cover which gives access to fans, memory, hard drive, so, cleaning it should be easier, 4 USB entries, a VGA port for an external monitor, 17'' 1080p, 16 GB of RAM, card reader, i7... there's only one problem so far, in which sometimes it won't turn on when only on battery (saw other complaints on the net about that too)... as I'm going to be mostly stationary, not that big of a problem for me (but it can be a dealbreaker for many).
So, first thing after getting the computer was changing the HD that came with it for an SSD. Really, this is not an upgrade that can be skipped if you're a software developer -- all your tools will be faster which is not only bound to make your life more pleasant, but also, it should pay for itself given your increased productivity.
Now, this was a huge stumbling block: it seems new computers don't have installation CDs with them anymore. No big deal I thought: just backup windows and restore in the new HD, but as it's smaller it was a no-go to. After other dead ends, what worked for me was putting the new HD in a USB HD case, getting http://www.easeus.com/ and doing a clone from one HD to the other. It's incredible how Microsoft/Lenovo managed to do something which should be very simple and straightforward (upgrading an HD) such a difficult thing (thankfully EaseUS TODO Backup made it much simpler -- provided you have a USB HD case lying around). I'll make sure I have a backup with everything configured there so that I don't risk loosing my Windows installation if some day the HD becomes trash.
Also, the computer came with Windows 8.1, which does seem a nice OS (my previous one had Windows 7). The only thing is that it does require quite some amount of customization to be usable... the start screen is really as bad as people say, but Windows 8.1 can be customized to boot directly to the desktop, so, I almost never see it. Also, Lenovo came with http://www.pokki.com/windows-8-start-menu, which I didn't know about, but seems a worthwhile replacement for the old Windows 7 start menu (so, I'm not really missing it thanks to pokki -- but I'd be considering going back to Windows 7 if it wasn't for it).
After that it was mostly a deal of getting my development environment in place and up to date (i.e.: TCC, Eclipse, LiClipse, Notepad++, Chrome, FTP, putty, pageant, plink, Git, Java, Python, VirtualBox, etc, etc). It does take a 1-2 days of work for me to set everything up -- but if the setup does hold for 4 more years, that's not so much in the end... time will tell :)
In the end, I'm really happy with the new toy!