More Storage: Available storage on Cloud SQL is increased to 100G.
Faster Reads: The maximum size of instances is increased to 16GB RAM, a 4 times increase.
Faster Writes: Additional feature of optional asynchronous replication is now offered, which gives the write performance of a non-replicated database, but the availability of a replicated one .This is further explained here -
When creating a Google Cloud SQL instance, you can choose to enable synchronous or asynchronous replication for your data. In either case, your data is replicated in multiple geographical locations within the EU or within the US. This is equivalent to taking a backup of any updates to your data as they happen. This means that in the very unlikely event of a complete failure of a datacenter, your data will be preserved.
In synchronous replication your updates are copied to multiple data centers before returning to the client. This is great for reliability and availability in the event of major incidents, but makes writes slower. The asynchronous replication option increases write throughput by acknowledging your write once it is cached locally, but before copying the data to other locations. Asynchronous replication results in faster writes to the database, because you don't have to wait for replication to finish, but you might lose your latest updates in the unlikely event of a data center failure within a few seconds of updating the database.
Choosing synchronous or asynchronous replication makes no difference to how much you are billed.
EU datacenter availability: Data can be stored and used in either Google's US or it's EU data centers. This is an important step given EU regulations on personal data.
Free Introductory Trial: Google is introducing a 6- month trial offer at no charge, effective until June 1, 2013. This will include one Cloud SQL instance with 0.5 GB of storage. You will need to Select D0 instances for introductory trial in the console
The billing tab of the Google APIs console shows you how much charge your Google Cloud SQL instances have gathered since the last bill was issued.
You can review the pricing and various options here. Your RDBMS in the cloud-now just another (free) API call away!