This is more of a public service announcement than anything else as it came up with a recent debug which I was doing for a field which was not present in Marketo but Saleforce was fine and all the correct settings were applied etc. Basically the varying versions of API's can add (or remove) fields or functionality as the system progresses - the current version is Version 36 but it would appear that Marketo appears to be using Version 20 (a whole 16 versions behind of current!).
For most this will not be an issue but where you get odd issues with fields not appearing and or not working - check the API version to see the changes as it may be a simple legacy call is the reason your connection is not working.
Salesforce supports all the versions of it's API, precisely because so many developers and mission-critical pieces of software rely on an old version.
Not really sure I understand the reply TBH my point is that Marketo accessing (using) a version of the API 16 versions behind the latest Salesforce API (version 36) therefore Marketo is not supporting a lof of new fields (and features) which are present in the latest. There are fields which are present in some objects which are not visible to version 20 (the Marketo access Partner API #)
To be 16 versions behind, for an app such as Marketo IMHO seems shocking.
My point is that there was not any risk on discontinuity of service. I had not gotten where you were coming from.
I am not sure that, with regards to objects supported by Mkto (Lead, account, contact, opportunity, campaign, campaign member and activities) this matters much. I would be interested with gap analysis if you have one.
From a Salesforce perspective yes - there is no issue re: compatibility but the fact Marketo is using an older version is detrimental to the fact Salesforce is increasing their feature sets etc. A quick API check of v20 and v36 show a few fields (on account in this case) which are now visible in the latest version which are invisible to Marketo (OtherStreet, Assistants Phone, Assistants Name to name a few).
While these fields may not be 100% valid for all it is a highlight of the APi differernces which it true for most objects.