Given that we're most likely to see a new phone later this year, the upgrades I can expect will be mostly internal (a more powerful SOC, 2GB RAM, 720p screen, possibly bigger internal memory). I can't see the shell changing as that would involve major retooling and breaking TOH compatibility.

Only 2 GB RAM and a 720p screen? I don't mind, that's plenty for me (I don't need loads of RAM and/or 1080p), but I can already see the outcry about such 'weak 2015 specs' on TMO and in the community as a whole (but esp. TMO)...

@vistaus
Actually it is the QUALITY of the components that matters(and lets Jolla down BIG time so far).
The screen of current Jolla is really bad, not because of the resolution, but because of low brightness(making it unreadable at sunny days), bad viewing angles, yellow stains etc. So 2GB and 720p are more than OK for me, but the overall quality of every Jolla component is lacking behind the C tier devices nowdays.
On the other hand - I really like how the OS is developing! I use a SONY Z3 compact with Lollipop, and I only prey for HW like it and SailfishOS on board!
Sailfish is completely on par with latest Android and has even better UI. It is the low quality HW that makes Jolla device lousy.

I like the Sony Z series as well my wife has one, I use the Jolla as daily driver. I really want more RAM. I agree the screen is very hard to read in bright daylight, I find myself having to shade it sometimes just to read it, don't remember that on my N9. I am using a memory card but I think we should have bigger onboard memory to cut down on problems with upgrades especially with btrfs. I also really want a more international modem. I hope the work on intel tablet will make it easier to use the intel more universal modem. This can help bring in NA developers, help those who travel regularly and those who move.

the nexus 5 with full brightness it still meh in bright daylight conditions

1. AMOLED,
2. Camera with good lens and stabilisation.....very important for me...!!!!!!!!!
3. 2GB RAM
4. Accessories (Cases) and more TOH's from Jolla
5. Better support for SD card (it is more software related)

Announced? Possibly. Released? I somehow doubt it.

Would you prefer a second Jolla, or a YotaPhone running Sailfish OS?

I mean, if you could only have one. Which is actually quite likely, because let's face it, Jolla are only in the hardware game right now because none of their 'partners' are brave enough to test the waters.

I'd like to see a J2, I'd like to see them build-on & refine, what they started with TOH, but this time be much more serious about it.
I'm not a fan of the YotaPhone concept, it's okay, but I don't want an e-Ink display permanently on the back of my smartphone.

However....
It'd be good to finally have a hw partner that's somewhat serious about contributing to the platform, & I'm sure there's folks out there who love the whole Yota concept.

2nd Jolla, it will go faster provided Jolla has resources. Software and Hardware guys sit closer together. Also, they'll make it nicer :P