The new HTC Tiara has good specs for a middling phone. If it’s priced similar to the Lumia 720, I think Nokia will have a good fight on its hands. If priced closer to the 820 but below it, I think it will fight against the 820. If priced closer to the 720, I believe it will win the fight against the 820 and will also fight against the 720. So yes, I think HTC is positioning this to compete with the two Lumias you mentioned.
The new HTC One is the most compelling and fresh design (especially the new BlinkFeed UI and Sense 5) from HTC that convinces me to fully support HTC from now on and spend on more and more HTC devices.
HTC Tiara Specs:
1.2GHz dual-core Snapdragon CPU
4.3-inch WVGA Super LCD2 display
8GB internal storage
8MP rear shooter (with 1.6MP FFC)
Windows Phone 8 GDR2