I've just decided that there's only one bad thing about my new phone, but it's kind of an important one.
Up to (and including) version 2.1 of Android, apps could only be installed on the phone's main memory. In other words, no matter how big your memory card (a 16Gb micro SD in my case), you were always limited in the amount of apps you could install by the phone's internal storage.
Now since Froyo (Android 2.2), apps can be installed on the SD card. However, for some reason, the app has to explicitly support it. Obviously, the majority of apps were written before Froyo was available, so they don't declare this ability.
My phone has 16Gb of external storage (the SD card) and a paltry 512Mb internal storage.
My phone is an HTC Desire, by the way. This is a fairly bad omission on HTC's part. When the phone was released (before Froyo), all apps had to fit in this 512Mb - alongside the operating system.
Now, unfortunately, I'll have to wait till version 3.0 and hope that any app can be installed to (or moved to) the SD card and that HTC will actually push it as an update for the Desire. (Although, at least it's hackable enough that I can put it on myself if I need to - invalidating my warranty of course.)