Sharepoint - What are the functions of a sharepoint architect?

As with most job titles this is very depend of the company in question.

When "developing" solutions to business problems using SharePoint the following comes into play (with a lot of extra work not included in this list):

1. Figure out what the business problem is
2. Find which part of it should be solved by IT if any
3. Figure out if SharePoint should be part of the solution
4. Figure out how the problem is best solved using SharePoint
5. Configure SharePoint to solve the problem
6. Define infra structure and custom "code" needed
7. Develop custom "code"
8. Set up infra structure

The boundaries are very gray but:

• Bullets 1-3 is Business analyst work
• Bullets 3-6 is SharePoint Architect work
• Bullets 5-7 is SharePoint Developer work
• Bullets 5+6+8 is SharePoint IT Pro work
• Making it look pretty is Designer work
• Leading this work is Project manager work

All of this requires different skills, but depending on the company it may end up under diffrent job titles and unfortnately in many companies being an Architect only means that you're the most senior developer so you should also be able to handle all of the other work.

Architects should know the ins and outs of SharePoint and know how to tackle a project from the best Microsoft-recommended approach. They should lead the team, and I've seen many act as their own Business Analyst when one is not available. They should be very independent. They should have the skills to do the job right, focusing on the long-term solutions.

I think architects, in comparison to SharePoint developers, should have a close relationship with the best practices and should be able to tackle any project that requires SharePoint. In my opinion, SharePoint architects, from my definition, have a better understanding of the supporting technologies that surround SharePoint, and thus grow outward in providing better ideas and solutions that are in support of SharePoint and not just SharePoint's entirety.

there are two roles for architect:
1) SharePoint Architect (Development)
He is basically responsible for, Mapping Client Requirements, Lead the team of developers, Solution Design, articulating solution risks and barriers, Recommending the Solutions, Plan,Prepare and execute the Project and all top level stuff.

2) SharePoint Architect (Infrastructure)
He is responsible for same thing but from Infrastructure side, what are the client requirement, suggest the Topology of Farm( how many servers), identifying what kind of services applications client needs, authentication requirement, capacity planning etc.

I am giving you the information on basis of what i observed in last couple of projects.