The E51 is without doubt the best phone I have ever owned, and this is down to its reliable, largely bug-free operating system, browsing connectivity speed and large expandable memory. It doesn't have quite such a repertoire of media functionality as some phones, but it rarely lets me down on any connectivity issues, which means no frustrating dropped calls or dropped internet connection.

It works well as a 3.5G modem too, and connects very easily via bluetooth to a laptop. The video camera was also a very pleasant surprise as it captures video very well indeed at a very good frame rate, considering it's a mobile phone.

Minor gripes are that the camera could be slightly better (it's a 2Mp) and the keys could be slightly bigger and better-spaced, but they feel very solid and responsive to the touch nonetheless.

Nokia seem to have really put a rocket up their business phone range...

As a business phone, it's absolutely fantastic. Only downfall is the camera. It's not as fast as you would like it nor as crisp. The images are quite poor compared to alot of the other generations of nokia phones with a 2MP camera.

Sound Quality, Battery Life, Build Quality is really good. Very impressed with it. It has some amazing WiFi range as well to be able to pick up networks from a far.

The Dictionary is a bit of a let down though. Once you use the "Spell" function and add a word in, every time you type in those letters, it becomes your predominant word even though you only needed to use it once. For example, you enter in gbp once (for british pounds) and next time you want to use the word "has", gbp will always come up first. Even if you use the "has" multiple times before you use "gbp", the order of preference doesn't change.

Tried a 4gb Micro SD HC card, worked like a charm!

A few pet peeves...
In your Messages, the names that appear ALWAYS show as Surname then First Name even though the address book is set to First Name then Surname.
When you're on a call, there's no way to get a live call duration without installing 3rd party software
You can't mark a selection of access points for deletion (if you've used WiFi in a lot of random places, you find that it adds the connection as an access point to your phone)
Can't set the browser cache to be on the SD card to allow for larger pages to load without a problem.

Other than that, the phone is magnificent. Absolutely love it!! Sturdy, yet thin and has all the functions you'll ever need. Battery life is excellent!

I bought this Nokia to replace my heavy weighted HTC TyTN II/T-Mobile MDA III. It has similar features but lacks the "heavyness" at nearly half the weight size. Having used a Mobile Windows powered phone, i found it difficult at first to use Symbian software, but its a breeze after a few days usage.

Picking up emails is easy but the screen size is not suitable for large or long emails, great for reading, but to reply can be awkward as there is not a full size keyboard, but you would not be buying it for this feature.

The 2MP camera is near useless, doesn't compare well with the 3MP i was used to on my previous phone, but again, its a usable feature that isn't there to lure you to buy the phone. Its the Wi-Fi, BT, slim size, lightness, being able to pick up emails on the go, PC sync, VoIP, and the freedom to add new software onto the phone that should attract you to buy it SIM free.

It even has IRDA, the old school infra red connectivity! One feature that appears to be unused in the UK, is PTT, push to talk, seen it in use in USA, but with UK people loving their text, i just think it will be wasted here.

The E51 uses Symbian 9 and Nokia's S60 (3rd Edition) therfore it is a real Smartphone. But it behaves and performs like a feature phone. Why does this matter? Well it is quick, unlike some Smartphones, and the additional short-cut keys make it very easy to use. The buttons provide good feedback and the Navi key is very responsive. But because it is a Smartphone you can install applications to customise its functionality. Business users will probably want the free Mail for Exchange applicaiton, free from Nokia, to allow full over the air synchronisation with a Microsoft Exchange server (and Push email capability). Also this tiny phone has WiFi and BT2, which means you have a lot of connectivity flexibility. And when away from WiFi the HSDPA (3.5G) will give you broadband like speeds. The BT is not just for BT headsets but also for connection to BT keyboard, like the Nokia model. With a BT keyboard and an upgrade of the free QuickOffice application suite, you have a very portable computer. And for those that care about looks, the silver and rose metal finish options make the E51 look very stylish. Overall a very small but powerful mobile computer.