I can't think of another neighborhood in the country undergoing as much change as Rincon Hill and the Transbay redevelopment district. What's actually under construction right now in each adjoining ~5 square block district:
Transbay Redevelopment District
1. Transbay Tower - 61 floors, 1,070 ft, 1,370,000 SF
2. 181 Fremont - 54 floors, 802 ft, 411,000 SF (and residences on top)
3. 350 Mission - 33 floors, 455 ft, 420,000 SF
4. 535 Mission - 27 floors, 378 ft, 307,000 SF
5. 222 Second - 26 floors, 370 ft, 430,000 SF
6. Foundry III - 10 floors, 150 ft, 285,000 SF
7. Transbay Terminal - $4B transit terminal designed by Cesar Pelli
Proposed - 50 1st St, two towers between 600-900 ft, possibly more.
3,223,000 SF of office space under construction on 6 different adjoining blocks. Of this, only 564,000 SF (17.5%) spoken for.
Rincon Hill
1. RH North Tower - 50 floors, 541 ft, 319 rentals
2. 399 Fremont St - 42 floors, ~460 ft, 452 rentals
3. 45 Lansing St - 39 floors, 430 ft, 320 rentals
4. Lumina Tower 1 - 40 floors, 400 ft, 655 condos in entire development
5. 340 Fremont - 40 floors, 400 ft, 348 rentals
6. Lumina Tower 2 - 35 floors, 350 ft, 655 condos in entire development
7. 299 Fremont - 32 floors, ~320 ft, 556 rentals in entire development
8. 333 Fremont - 8 floors, ~80 ft, 83 rentals
Between these towers you have 2,078 new rentals and 655 new condos, all rising together.