I have click the 'update' tab in LR3.6 and it advises me that I am up to date.Is LR 4.1 so vastly different that free updates don't apply?
To go to LR 4.1 from 3.6, you'll need to purchase an upgrade. They're about $80 US . Whenever the version number before the decimal point changes, it costs money to move on.
You can download a trial version of 4.1, play with it for 30 days, and then decide whether it's worth the price.
Note: you need to be running Windows Vista or Win 7 (or if you have a Mac, Snow Leopard in 64-bit) to run LR 4.x
LR 4.1 is a New paid upgrade. Some new features, New Process engine, improved rendering of raw files, two new modules Book and Map. Have a look at the Adobe site.
There are still very many issues preventing LR 4 from working smoothly as 3.6 does.
No there aren't!
You might have problems, but - try as you might to persuade everyone of this - they are not universal.
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