In reading through all the replies here, I just had to respond to this one as it's completely misinformation (no offense).
To get one thing straight, the WIRED INTERNET latency within the US in the "absolute worst case" is roughly 100ms. That's coast to coast latency from an extreme all the way on the West Coast, to East Coast Canada, & additionally factoring in transit to your ISP, such as CableModem or even a DSL connection w/ 8ms symmetric Interleaving ENABLED.
For everyone's viewing reference, here's three traces that I've run for you off of machines in different Los Angeles datacenters. If your route looks worse than this, especially if you're closer to the server, I'd strongly urge you to complain to your ISP as something is very-wrong.
--150ms I could believe for a player playing from Arizona, using a home-agent in LA, and running on 4G cellular internet. Yet as you can see, you have to try pretty hard to think up scenarios where such latency is attained. Eg, delving into wireless internet.
The "worst case" US player's latency on a land-line internet connection is equal to the "best case" EU player's connection. I'm sorry, but all NA players did win out on it internet-path / distance wise (between the two regions being serviced by SE's location choice). There's no way for a connection through international fiber to remotely compare, especially in terms of multi-peering & general route choices in the case of failover or total bandwidth.
NOTE: Similar latency routes exist from Washington as well, and also West Coast Canada (which is lower than West Coast US).
MultaCom
MTR [v0.85]
Wed Aug 20 06:23:10 2014
Host Loss% Snt Last Avg Best Wrst StDev
1. 2-126-52-198-static.reverse.quer 0.0% 29 0.0 0.0 0.0 0.1 0.0
2. 198.211.19.9 0.0% 29 0.5 15.9 0.3 223.2 44.4
3. tge4-1.cr2.lax.multacom.com 0.0% 29 0.3 3.0 0.3 29.5 7.4
4. ix-5-2-3-0.tcore1.LVW-Los-Angele 0.0% 28 0.4 2.9 0.3 62.5 11.8
5. if-3-2.tcore1.PDI-Palo-Alto.as64 96.3% 28 82.7 82.7 82.7 82.7 0.0
6. if-2-2.tcore2.PDI-Palo-Alto.as64 0.0% 28 83.2 83.2 82.9 86.2 0.6
7. if-11-3.tcore2.CT8-Chicago.as645 0.0% 28 82.7 83.0 82.6 87.0 0.9
8. if-3-2.tcore1.W6C-Montreal.as645 0.0% 28 82.7 83.2 82.7 93.5 2.0
9. 66.198.96.50 0.0% 28 83.9 83.5 83.1 85.1 0.4
10. 192.34.76.2 0.0% 28 83.3 84.1 83.1 108.2 4.7
11. 199.91.189.234 0.0% 28 84.0 84.6 83.1 100.7 4.0
12. 199.91.189.47 0.0% 28 83.0 83.3 83.0 85.7 0.5
InterNAP
Wed Aug 20 03:27:42 2014
Host Loss% Snt Last Avg Best Wrst StDev
1. border1.te4-4.nuclearfallout-64. 0.0% 41 0.5 5.9 0.4 184.1 28.7
2. core2.po2-20g-bbnet2.lax015.pnap 0.0% 41 1.6 1.6 1.4 3.2 0.3
3. xe-2-2-0.er4.lax112.us.above.net 4.9% 41 1.1 3.5 0.9 48.2 9.5
4. ae10.cr2.lax112.us.above.net 0.0% 40 1.2 5.6 1.1 33.2 8.7
5. ae12.mpr1.lax12.us.above.net 0.0% 40 1.1 1.5 1.0 14.4 2.1
6. ae7.edge2.LosAngles.Level3.net 10.0% 40 1.2 1.5 1.1 12.4 1.9
7. vlan80.csw3.LosAngeles1.Level3.n 0.0% 40 74.5 74.8 74.4 85.8 1.8
8. ???
9. ae-3-3.ebr3.Dallas1.Level3.net 0.0% 40 74.3 74.5 74.2 76.6 0.5
10. ae-93-93.csw4.Dallas1.Level3.net 0.0% 40 74.2 74.5 74.1 85.6 1.8
11. ???
12. ae-14-14.ebr2.Chicago2.Level3.ne 0.0% 40 74.4 74.4 74.3 75.6 0.3
13. ae-1-100.ebr1.Chicago2.Level3.ne 0.0% 40 74.3 74.4 74.2 76.1 0.3
14. ???
15. ae-10-10.car2.Montreal2.Level3.n 0.0% 40 74.2 116.3 74.2 276.5 62.9
16. ORMUCO-COMM.car2.Montreal2.Level 0.0% 40 75.0 75.0 74.9 75.3 0.1
17. ???
18. 192.34.76.2 0.0% 40 77.9 79.7 77.8 124.7 8.1
19. 199.91.189.234 0.0% 40 79.1 79.3 78.0 113.3 5.7
20. 199.91.189.47 0.0% 40 78.1 78.1 77.9 78.2 0.1
Corporate Colo
Wed Aug 20 10:10:29 2014
Host Loss% Snt Last Avg Best Wrst StDev
1. 74.124.208.129 0.0% 23 0.7 0.7 0.7 0.8 0.0
2. 205.134.242.113 0.0% 23 0.3 0.4 0.3 0.5 0.0
3. 74.124.220.141 0.0% 23 0.4 0.7 0.3 7.4 1.5
4. po10-dc1-core-1.corporatecolo.co 0.0% 23 0.5 5.1 0.3 108.0 22.4
5. xe-5-0-5.ar1.lax2.us.nlayer.net 0.0% 23 4.2 8.6 1.8 31.6 6.2
6. ae0-50g.cr1.lax2.us.nlayer.net 0.0% 23 0.3 4.2 0.3 53.3 12.3
7. ae6-214.lax20.ip4.gtt.net 0.0% 23 0.4 0.4 0.3 1.0 0.0
8. xe-1-0-0.mtl10.ip4.gtt.net 0.0% 22 73.1 74.9 73.0 113.6 8.6
9. ormuco-gw.ip4.gtt.net 0.0% 22 73.7 73.5 73.4 73.7 0.0
10. 192.34.76.2 0.0% 22 73.5 74.0 73.5 78.9 1.3
11. 199.91.189.234 0.0% 22 73.8 73.8 73.8 74.0 0.0
12. 199.91.189.47 0.0% 22 73.6 73.7 73.6 73.9 0.0
This all said ... I'm NOT saying a west-coast US location would be a bad idea, especially for servicing "Oceanic" English speakers without forcing them to play on the Japanese server clusters. However, EU players DO need a closer datacenter choice to cover the outskirts and to provide a pleasing to play experience.