I was going to post this post on the SamsungblogSA but after I got to upload the 8th image, which was such a tedious process and it gave me a 502 error, I just gave up. So here is my edited article, which tells you what works on the i8910HD and how to get the best our of it.
Note: HX-V7 is out. Yes my writeup started a month or so ago and the guy has already moved on to V7, which comes with support for Symbian3 found on the Nokia N8
...
There are a few modified firmware options available like the HypeX HX-V5 (V7 is now out) and HelloOX. I decided to install the HyperX HX-V5 firmware. The upgrade took me 13 minutes to do, only because it took me 10 minutes to figure out which button was the lock button, so that I could get to the boot-up screen. The i8910HD documentation called the button I was looking for, the "hold" button. So what do you get when you install the HyperX HX-V5 firmware (a modification of the last & final firmware update Samsung did)?
Pros:
* Faster phone - moving between screens are a lot snappier and loading of your gallery is also improved.
* Threaded SMS-Lite - You can now read your sms in threads, which makes a lot more sense that having a seperate received & sent folder for me.
* All menus have landscape mode
* Kastor Effects - additional to original K-Effects
* Turbo Mode - Optional, using full 600Mhz processor
* 3D icons - added to collection
* Ringtones - New
* Widgets - CirskeloFlipClock Widget added
* Filebrowser - updated
* Homescreen Nav-Bar - Transparent
* Quick-Office - Updates working
* 720p Recording - Pause your recording & continue and your recording sound will be synced.
* Photos - improved jpeg codec
* My Media App - Like a video wall for media apps. See now point in this. Would have been great for your galleries.
* Home Screen Themes - Full page & Navigation bar added
Cons:
* Removed the between screens finger swipe navigation (working now, might have been a bug)
* Removed the Photo contacts (see below how to reinstall)
* Removed 3D Navigation (see below how to reinstall)
* Games removed
Themes:
The following works for the i8910HD and I think they are great.
HTC Desire
http://www.zedge.net/themes/743685/htc-desire-hd-by-grk-theme/
HTC Hero
http://www.zedge.net/themes/745292/htc-hero-hd-by-grk-theme/
The following programs are a must install. Some are free, others you can download a trial to test it and others you have to pay for.
Nimbuzz (free - like Skype/ but better)
http://www.nimbuzz.com/en/mobile/download
Opera Mobile 10.1b (better than Opera Mini)
http://www.opera.com/download/get.pl?sub=++++&id=33062&location=270¬hanks=yes
OVi Store Patch (Now you can download for free or buy symbian apps)
http://hx-custom-roms.com/?page_id=5
Play, Previous, Next (Put your music players control on your SPB Mobile interface)
SPB Mobile Shell 3.05 (295) - (Trial - awesome, although it takes you speed back to your original software, but worth it. There is always Turbo Mode)
http://www.spbsoftwarehouse.com/symbian-software/mobileshell/download.html
Vlingo (Trial)
http://www.vlingo.com/download-nokia.jsp
Gmail Mobile (free)
http://www.google.com/mobile/mail/
RoadSync (Sync with Google Calendar, etc. Need to buy the upgrade to make it work properly +-$9)
http://www.dataviz.com/products/roadsync/series60/index.html
Modify your SPB Mobile Shell
http://forum.dailymobile.se/index.php/topic,23964.0.htm
Firmware
http://hx-custom-roms.com/
Flash Tutorial
http://hx-custom-roms.com/?cat=8
Photo Contacts
http://hyperx.garrettcullum.com/photocontacts.sis
PS: My memory is a bit rusty. The two themes mentioned and the OVi patch might be included in the firmware upgrade.