Here is a link to the HTC support forum for the thunderbolt and this user funkyb in the 9th post down says that using some type of dev tool you can see all the memory used and that we do have 8GB but it is used for data.
I understand it but at the same time I don't like it. I know 2.5GB is a lot of space but at the same time thinking I was getting 8GB for app storage instead of the small amount I was used to on the OG droid. Having 8GB of onboard storage really help to make my mind up about this phone instead of waiting on the bionic. I know they never said it had 8GB of app storage but when you see it posted as 8GB internal memory I only assumed that most of it would be available to me for storage for apps, emails, sms, mms and anything else I felt like putting on my phone.
Here is the link
Almost 70% of Internal Memory is Missing. - HTC Thunderbolt (Verizon) - Android Forums - HTC Community
If you want to read it here instead of going to HTC site here is the post.
Posted by funkyb
on 22 Mar 2011 6:53 AM
* rated by 0 users
* Re: Almost 70% of Internal Memory is Missing.
*
I don't agree with the earlier poster saying it does not have 8GB. Below is the real scoop, but first I want to note that this morning I received an email from HTC confirming the below analysis is correct. An android developer took a look at this issue for me using debug tools. He queried the actual internal file system. The block below shows what he found: ******************************************************************** $ export PATH=/data/local/bin:$PATH $df /dev: 305764K total, 0K used, 305764K available (block size 4096) /system: 869884K total, 401260K used, 468624K available (block size 4096) /data: 2734896K total, 380720K used, 2354176K available (block size 4096) /cache: 434916K total, 34844K used, 400072K available (block size 4096) /devlog: 21100K total, 4132K used, 16968K available (block size 4096) /mnt/asec: 305764K total, 0K used, 305764K available (block size 4096) /app-cache: 8192K total, 504K used, 7688K available (block size 4096) /mnt/sdcard: 31154688K total, 639936K used, 30514752K available (block size 32768) /mnt/secure/asec: Permission denied /mnt/asec/com.rovio.angrybirdsseasons-1: 18688K total, 16704K used, 1984K available (block size 4096) $ Those are from mine. Looks like the 8gb is there just spread out across file systems. *********************************************************************** Now if that looks like gobbly good to you, here's how to interpret the results: Ignoring the fact that 1 GB = 1024 MB = 1,048,576 KB, ignoring the mounted SD card (/mnt/sdcard/), and using powers of 10 to keep this simple: The above adds up to about 4.7GB. This means the other 3.3 GB is on the 'access denied' branch shown above (/mnt/secure/asec/) and/or on the recovery partition (which might be the same thing as /mnt/secure/asec/). This seems perfectly reasonable to me, and is a normal way to set up the file system. Furthermore, here is an excerpt from my conversation with HTC. I've removed a lot (related to other issues, and also has personally identifiable info): ================================ ...the HTC Thunderbolt has 8 GB of internal memory. However, most of that memory is put aside for the phone's operating system, messages(text, picture, email, etc), built in applications, etc. This means that you will not see the full 8GB available.... ================================ This confirms the developer's analysis shown above, and an interesting corollary to take away from this is that storage required for messages, pictures, email, built-in-app-data, etc, DOES NOT use up any of the 2.7 GB we are seeing. The 2.7 GB we are seeing is the 'do what you want with it' storage for other items. The rest is reserved for operating system files, built-in-app-data, the recovery partition, etc... I consider this issue resolved to 100% satisfaction.