What you pay for in Azure can be a bit confusion, though the recent changes in terminology actually makes it a lot clearer now. (or maybe I just know what they mean this time)
Here is my experience based what I have been paying...
Note: This is as of April 2015. Azure is in constant change so these may change later.
Free website is a single free website. Nice and simple.
Shared is also a single website with a pay by the minute charge.
When creating a website that uses a paid service such as a BASIC Small web app then it is not just a single website you are getting and paying for. Its like you are getting a virtual server to host all your web apps on. Once you've created your £35 per month website you can then add hundreds of websites to that same service plan and still only pay the £35.
When you create a new website you need to pick the service plan it will fall under.
You can have multiple plans ie some free website, basic small, standard, large etc. but you pay for each plan in use.
Payment in each plan is on a per minute and per instance basis.
If configured, instances will scale up sites when demand gets high. Each instance that is running incurs a charge. If demand is very high and it runs up 3 instances for 10 minutes then for that 10 minutes you will pay 3 times the rate of the plan.
When you create an SQL database then an SQL server is created for it to sit in. When adding further databases you can add them to the same server.The costing unlike the web sites is per database. The server is there for management not payment.Payment is billed by the minute for each database regardless of the state of the database.
If doing heavy processing then the database can be ramped up to a higher spec during that period and brought down afterwards. Costing for the high spec will be for the number of minutes it was in use. For me on the North Europe server it took about 5 minutes to jump between specs if in same service tier (eg S1 to S3 in STANDARD)
If your managing lots of saas databases then Elastic databases has just come out for preview which will move resources around and cut your costs.
There is also cost for transferring data. Data transferring between Azure services like a database and website are free provided they are on the same region.
The cost of data going into Azure is free (publishing website, user upload of documents etc.)
The costs of data leaving Azure is free for the first 5Gb then its per Gb after that.
If running a website with a large amount of data going to users then you may have to worry about this charge. There is no service charge cap yet in Azure either.
Its pretty much free. Have run the whole companies development off it instead of dedicated onsite servers with TFS. Works really well and I don't see the need to have an onsite TFS server set up ever again for my level of use.
With a MSDN subscription you get access to everything. Includes all source control, backlog management and the test management and running.
You can have 5 basic users for free. They have access to the projects backlog management and due to a recent change the basic user can run tests. However they cannot create test plans.
The advanced user is required if you want a tester (without MSDN sub) to create some test plans. You pay by the month which was £45.08 until I stopped it due to them giving the basic user free test run abilities.
The Networking 3p cost is the charge I got because I went above the 5Gb outbound data allowance by .577 Gb
Advanced users is the charge for one extra users for Visual studio online.
I must have been testing a S2 database on this month as I used 0.8 days worth which cost me 12p otherwise I was just over £18 for the months S1 database usage I usually have.
I have three websites in use as I was doing some upgrade/downgrading during testing. Their unit is hours. It cost me a penny for a quick 8 minute test in the large website.
The prices shown are all ex Vat. All but the advanced user was covered by the MSDN subscription so it was all kind of free.