SuperSoph_WD :
Hey there, dg27!
Both WD Black HDDs are in the 7,200 RPM class. I'm not sure which specifications sheets are you referring to but I will share the official ones from our website:
WD1002FAEX
WD2003FZEX
It's possible that the drives might seem a bit hotter due to the fact that they are performance drives. Their operating temperature shouldn't exceed 60° C and, respectively, their non-operating temps shouldn't go above 70° C.
Those WD Blacks that are in the enclosures don't get any extra component cooling from the PC fans as those that you have in the SATA ports in your system. I don't think you have anything to worry about, as long as the temps don't exceed their normal range.
If you have any concerns about their health, you should use
WD's Data LifeGuard Diagnostics to monitor their S.M.A.R.T. data by running the QUICK & the EXTENDED tests.
Make sure you always keep multiple backups of your data, as this is the best way to avoid any potential data loss.
Hope this was helpful. Keep me posted if you have further questions!

SuperSoph_WD
Thanks for your reply.
I'm a long time WD Black user and have about 12 across two desktops, both as primary data drives and redundant backups. I'm very familiar with both the WD literature and the proprietary WD diagnostic tools.
I was referring to the readings from
Speccy, which is a generally highly regarded monitoring program from Piriform (the people who make CCleaner).
Here's the data from the summary page for my system. The two drives I was talking about are
the last two listed:
Operating System
Windows 7 Professional 64-bit SP1
CPU
Intel Core i7 960 @ 3.20GHz 59 °C
Bloomfield 45nm Technology
RAM
24.0GB Triple-Channel DDR3 @ 666MHz (9-9-9-24)
Motherboard
Dell Inc. 05DN3X (CPU 1) 42 °C
Graphics
HP LP2475w (1920x1200@59Hz)
HP LP2475w (1920x1200@59Hz)
2047MB NVIDIA GeForce GTX 960 (EVGA) 45 °C
Storage
476GB Samsung SSD 840 PRO Seri (SSD) 38 °C
1863GB Western Digital WDC WD2002FAEX-007BA0 (SATA) 43 °C
3726GB Hitachi HGST HDS 724040ALE640 USB Device (USB (SATA)) 36 °C
1863GB Western Digital WDC WD2003FZEX-00Z4SA0 (SATA) 41 °C
1863GB Western Digital WDC WD2002FAEX-007BA0 (SATA) 38 °C
2794GB Western Digital WD My Book 1230 USB Device (USB)
3725GB Western Digital WD My Book 1230 USB Device (USB)
931GB Maxtor OneTouch IEEE 1394 SBP2 Device (SATA)
3726GB ASMT 2115 USB Device (USB (SATA)) 41 °C
931GB Western Digital WDC WD10 02FAEX-00Z3A0 USB Device (USB (SATA)) 45 °C
1863GB Western Digital WDC WD20 03FZEX-00Z4SA0 USB Device (USB (SATA)) 45 °C
29GB Lexar USB Flash Drive USB Device (USB)
Optical Drives
PLDS DVDRWBD DH-12E3S
ASUS DRW-24B1ST j
Audio
Avid Mbox
Here's the data for my newest Black drive. The RPM is correctly shown as 7200:
WDC WD2003FZEX-00Z4SA0
Manufacturer Western Digital
Form Factor TB/3.5-inch (new format)
Heads 16
Cylinders 243,201
Tracks 62,016,255
Sectors 3,907,024,065
SATA type SATA-III 6.0Gb/s
Device type Fixed
ATA Standard ACS2
Serial Number WD-WCC1P3FCE173
Firmware Version Number 01.01A01
LBA Size 48-bit LBA
Power On Count 26 times
Power On Time 10.0 days
Speed 7200 RPM
Features S.M.A.R.T., NCQ
Max. Transfer Mode SATA III 6.0Gb/s
Used Transfer Mode SATA II 3.0Gb/s
Interface SATA
Capacity 1863 GB
Real size 2,000,398,934,016 bytes
RAID Type None
Here's the same data for the two drives in question. The RPM is shown as 10,000.
WDC WD10 02FAEX-00Z3A0 USB Device
Manufacturer Western Digital
RPM/Buffer Size or Attribute 10,000 RPM with 16 MB cache
Interface/Connector SATA III 6 Gb/s
Heads 16
Cylinders 121,601
Tracks 31,008,255
Sectors 1,953,520,065
SATA type SATA-III 6.0Gb/s
Device type Fixed
ATA Standard ATA8-ACS
Serial Number WD-WCATR5393883
Firmware Version Number 05.01D05
LBA Size 48-bit LBA
Power On Count 1513 times
Power On Time 888.5 days
Speed 10000 RPM
Features S.M.A.R.T., AAM, NCQ
Max. Transfer Mode SATA III 6.0Gb/s
Used Transfer Mode SATA III 6.0Gb/s
Interface USB (SATA)
Capacity 931 GB
Real size 1,000,204,886,016 bytes
RAID Type None
WDC WD20 03FZEX-00Z4SA0 USB Device
Manufacturer Western Digital
RPM/Buffer Size or Attribute 10,000 RPM with 16 MB cache
Interface/Connector SATA III 6 Gb/s
Heads 16
Cylinders 243,201
Tracks 62,016,255
Sectors 3,907,024,065
SATA type SATA-III 6.0Gb/s
Device type Fixed
ATA Standard ATA8-ACS
Serial Number WD-WCATR5393883
Firmware Version Number 05.01D05
LBA Size 48-bit LBA
Power On Count 1513 times
Power On Time 888.5 days
Speed 10000 RPM
Features S.M.A.R.T., AAM, NCQ
Max. Transfer Mode SATA III 6.0Gb/s
Used Transfer Mode SATA III 6.0Gb/s
Interface USB (SATA)
Capacity 1863 GB
Real size 2,000,398,934,016 bytes
RAID Type None
My question was really directed at those familiar with this program (Speccy). I have never known the data to be wrong.