The Z10 is a good smartphone. Frankly, it's a better smartphone than I expected from RIM at this stage in the game. It does everything a modern phone should do, usually without hesitation. It doesn't do everything perfectly, but it does many things — most things — reasonably well.
The problem with the Z10 is that it doesn't necessarily do anything better than any of its competition. Sure, there are arguments that could be made about how it handles messages or the particulars of its camera, but no one could argue that there's a "killer app" here. Something that makes you want or need this phone because it can do what no other phone can do. That's not the case — in fact if anything is the case, it's that the Z10 can't yet do some things that other devices can. Or at least, can't do them quite as well.
And that's where I end up. The Z10 is a fine device, well made, reasonably priced, backed by a company with a long track record. But it's not the only device of its kind, and it's swimming against a massive wave of entrenched players with really, really good products. Products they figured out how to make years ago. Products that are mature. The smartphone industry doesn't need saving.
If you love RIM and the BlackBerry brand and really want to keep supporting them, buying a Z10 wouldn't be a mistake. But I think there are better phones on the market, and I don't yet see a compelling reason for most customers to choose this phone over those better ones. So why the Z10? Why now? Until BlackBerry can answer that question, I would be careful about how you spend your money.