I had an argument with my colleagues over the difference between 32-bit and 64-bit Excel 2007. I said the main difference is that in 64-bit version, we'll be able to add more than 65536 rows where as in 32-bit we won't be able to add more than 65536 rows.
Please clarify this.
No, both 32 and 64 bit versions support more than 65536 rows, and have done since Excel 2007 was released.
The main difference is that you can work with very large workbooks in the 64 bit version. The downside of the 64 bit version is that, at present, there is poor support from 3rd party add-ins.
Update
This was written back in 2011. I'm sure that support for 3rd party add-ins is better now. However, it may still be an issue, and before installing the 64 bit version it is worth checking that all your required tools that are built on top of Excel are compatible with the 64 bit version.